subject:(Stars Evolution)

University of Victoria

1. Lyder, David Anthony. Star formation in Camelopardalis: Cam OB1.

Degree: Department of Physics and Astronomy, 2018, University of Victoria

URL: https://dspace.library.uvic.ca//handle/1828/9769

► Star formation in the Cam OB1 region is investigated. Star formation, in general, is considered in terms of three elements: a) the structural relationship between… (more)

▼ Star formation in the Cam OB1 region is investigated. Star formation, in general, is considered in terms of three elements: a) the structural relationship between the parent molecular clouds and newly formed stars, b) the temporal evolution of the parent molecular clouds, and c) the probability of the occurrence of star formation. Star formation in Cam OB1 over the range in l and b considered in this work, is concentrated in the vicinity of Cam R1 and appears to have led to the formation of three distinct stellar groups: a) Group I. formed ~ 1 - 50 x 106 yr ago, and located spatially and kinematically between two CO complexes, b) Group II. formed ~ 1 - 3 x 106 yr ago. and coincident with one of the previously mentioned complexes, and c) Group III. the youngest group, formed ~ I - 20 x 104 yr ago, and located at the current point of intersection between the two complexes in (a). The mass function (MF) for Groups I and II is similar to the cloud mass function of the parent molecular clouds, i.e. a power-law with exponent α ~ 2. A similar analysis for the Group III stars and associated molecular clouds cannot be performed due to the relatively small numbers in both samples. The star forming efficiency (SFE) in all cases is ~ 1%. It is proposed that cloud-cloud collisions between the CO complexes in the region triggered the formation of Groups I and III, while Group II was produced by a shock induced by the radiation pressure and stellar winds from the stars in Group I. An analysis of the molecular cloud structure in Cam OB1 and the background Perseus arm also shows that the clouds in both regions are turbulent, and typical of clouds seen elsewhere in the Galaxy. However, the clouds in Cam OB1 show a large dispersion in the degree with which they are self-gravitating, with the larger, warmer clouds being gravitationally bound. The principal data set for this work comprises fully sampled [special characters omitted] observations of the western half of Cam OB1, which were obtained at the Center for Astrophysics during the winter of 1992-1993. These data have an effective resolution of 10', a velocity resolution of 0.65 km s-1, and a sensitivity of 0.115 K. High resolution (20") observations of the [special characters omitted] transition of the most active star forming region were obtained with the James Clerk Maxwell Telescope during the winter of 1994-1995. These observations led to the discovery of a second outflow. AFGL 490 – iki, associated with IRAS 03234+5843, in the immediate vicinity of the very well-studied molecular outflow AFGL 490. Additional observations of the [special characters omitted], taken with the 26m telescope at the Dominion Radio Astrophysical Observatory during the fall of 1994, did not reveal any such masering activity in the Cam OB1 region, but did lead to the discovery of a new maser, associated with IRAS 02455+6034. in the background Perseus arm. Advisors/Committee Members: Gower, A. C. (supervisor), Purton, C. R. (supervisor).

Subjects/Keywords: Stars; Evolution

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lyder, D. A. (2018). Star formation in Camelopardalis: Cam OB1. (Thesis). University of Victoria. Retrieved from https://dspace.library.uvic.ca//handle/1828/9769

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lyder, David Anthony. “Star formation in Camelopardalis: Cam OB1.” 2018. Thesis, University of Victoria. Accessed March 08, 2021. https://dspace.library.uvic.ca//handle/1828/9769.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lyder, David Anthony. “Star formation in Camelopardalis: Cam OB1.” 2018. Web. 08 Mar 2021.

Vancouver:

Lyder DA. Star formation in Camelopardalis: Cam OB1. [Internet] [Thesis]. University of Victoria; 2018. [cited 2021 Mar 08]. Available from: https://dspace.library.uvic.ca//handle/1828/9769.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lyder DA. Star formation in Camelopardalis: Cam OB1. [Thesis]. University of Victoria; 2018. Available from: https://dspace.library.uvic.ca//handle/1828/9769

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Hong Kong

2. Wong, Ka-tat. SiO-emitting condensations throughout the envelope of the yellow hypergiant IRC+10420.

Degree: 2013, University of Hong Kong

URL: http://hdl.handle.net/10722/195970

► IRC+10420 is a massive (> 20M☉), very luminous (> 〖10〗^6L☉) star that is in the rare phase of evolution from the red supergiant to the… (more)

▼ IRC+10420 is a massive (> 20M☉), very luminous (> 〖10〗^6L☉) star that is in the rare phase of evolution from the red supergiant to the luminous blue variable or Wolf-Rayet phase. Previous observations reveal that the circumstellar envelope is rich in molecular gas, and can be detected out to a radius of about 8” = 6.0 X 〖10〗¹⁷ cm. Observations in CO also reveal that the global massloss rate of IRC+10420 has changed dramatically over the last 6000 years, comprising two major episodes of mass loss lasting for about 1000 and 4000 years respectively separated by period of very low mass-loss rate lasting for about 1000 years. Surprising, previous observation in SiO(J = 2 - 1) revealed a ring-like enhancement at a radius of about 1” (7.5X 〖10〗¹⁶ cm) from the star, contrary to the expectation that SiO molecules should be frozen onto dust grains very close to the star (within ～〖10〗^16cm). This ring-like enhancement has been attributed to a large-scale shock produced by interactions between faster and slower moving portions of the expanding envelope. In this thesis, we mapped the circumstellar envelope in SiO(J = 1 - 0) to better constrain the physical conditions (gas density, temperature and SiO abundance) in the SiO-emitting gas. We find a similar ring-like enhancement in SiO(J = 1 - 0) but located further out at a radius of about 2” (1.5 X 〖10〗¹⁷ cm), and confirm that the SiO emission extends as far out as the CO envelope. The computed SiO(J = 2-1)/SiO(J = 1-0) line ratio significantly exceeds unity at radius out to about the location of the ring-like enhancement (2”), and drops to a value of about unity beyond this radius. From a one-dimensional non-local thermodynamic equilibrium model, we explore the physical conditions that can reproduce the observed brightness temperatures in both SiO(J = 10) and SiO(J = 2-1) as well as their line ratio as a function of radius. The SiO-emitting gas is required to have a density that is much higher (from a factor of a few to about two orders of magnitude) than has been inferred for the CO-emitting gas at the same radii. The required surface filling factor of the SiO-emitting gas depends on their unknown gas-phase SiO abundance; for an abundance of ～〖10〗^(-5), as inferred just above the photospheres of lowmass evolved stars, the surface filling factor of these condensations range from ～0.001 to ～0.1. Thus, the SiO emission from the envelope of IRC+10420 most likely originates from dense condensations that are immersed in more diffuse gas that produces the bulk of the observed CO emission. We reason that the SiO-emitting condensations correspond to the dust clumps detected in reflected light with the Hubble Space Telescope. These dust clumps are distributed from near the star out to a radius of 2”, spanning the same extent as the peaks of SiO- (and CO-) emitting envelope. We show that these dust clumps are expanding in every direction away from the stars at a velocity that is significantly higher than the CO-emitting gas, and anticipate that shocks thus generated heats up the dust… Advisors/Committee Members: Lim, JJL (advisor).

Subjects/Keywords: Stars - Evolution

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wong, K. (2013). SiO-emitting condensations throughout the envelope of the yellow hypergiant IRC+10420. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/195970

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wong, Ka-tat. “SiO-emitting condensations throughout the envelope of the yellow hypergiant IRC+10420.” 2013. Thesis, University of Hong Kong. Accessed March 08, 2021. http://hdl.handle.net/10722/195970.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wong, Ka-tat. “SiO-emitting condensations throughout the envelope of the yellow hypergiant IRC+10420.” 2013. Web. 08 Mar 2021.

Vancouver:

Wong K. SiO-emitting condensations throughout the envelope of the yellow hypergiant IRC+10420. [Internet] [Thesis]. University of Hong Kong; 2013. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10722/195970.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wong K. SiO-emitting condensations throughout the envelope of the yellow hypergiant IRC+10420. [Thesis]. University of Hong Kong; 2013. Available from: http://hdl.handle.net/10722/195970

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Arizona

3. Adams, Mark Thomas. AN OBSERVATIONAL STUDY OF LOW-MASS STAR FORMATION IN NGC 2264 .

Degree: 1981, University of Arizona

URL: http://hdl.handle.net/10150/282033

► The history of an actively star-forming region, containing the young, open cluster NGC 2264, is examined in this thesis using UBVRIHα photographic plate material. After… (more)

▼ The history of an actively star-forming region, containing the young, open cluster NGC 2264, is examined in this thesis using UBVRIHα photographic plate material. After digitization and removal of the variable background from these plates, automatic detection and photometry algorithms yield magnitudes for a set of candidate low-mass cluster members. Using the photographic plates and a supplementary video camera Hα survey, these candidates are selected on the basis of their exhibiting significant Hα emission, large amplitude variability, or anomalously blue colors. To study the age spread in NGC 2264, a theoretical H-R diagram is constructed. Infrared photometry of 33 candidate members permits an evaluation of the bolometric luminosities of these stars; the unreddened (V - R) and (V - I) colors yield effective temperatures. The theoretical mass tracks and isochrones of Cohen and Kuhi (1979) are adopted and extrapolated to lower luminosities and temperatures. The effects of circumstellar dust and gas shells on the location of the NGC 2264 stars in the H-R diagram are examined. No systematic biases in the derived bolometric luminosities and temperatures are found. The optical and infrared excesses of these stars are found to be uncorrelated, requiring separate mechanisms for their generation. A gaseous envelope is most likely the source of the optical excess; thermal emission from hot dust most probably leads to the observed infrared excesses. An age spread for the low-mass NGC 2264 stars of ≳10⁷ years is indicated. Star formation in NGC 2264 is found to have proceeded sequentially as a function of mass and time. Low-mass star formation began ∼2-3 x 10⁷ years ago, peaked ∼4-5 x 10⁶ years ago, and declined thereafter. Star formation at successively higher masses has started, peaked, and then declined at successively younger ages. No significant differences are seen between the field and NGC 2264 luminosity functions to the faintest levels observed (Mᵥ ≈ +11). There is no evidence for a low-mass turnover in NGC 2264. Advisors/Committee Members: Strom, Stephen (advisor).

Subjects/Keywords: Stars – Evolution.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Adams, M. T. (1981). AN OBSERVATIONAL STUDY OF LOW-MASS STAR FORMATION IN NGC 2264 . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/282033

Chicago Manual of Style (16^th Edition):

Adams, Mark Thomas. “AN OBSERVATIONAL STUDY OF LOW-MASS STAR FORMATION IN NGC 2264 .” 1981. Doctoral Dissertation, University of Arizona. Accessed March 08, 2021. http://hdl.handle.net/10150/282033.

MLA Handbook (7^th Edition):

Adams, Mark Thomas. “AN OBSERVATIONAL STUDY OF LOW-MASS STAR FORMATION IN NGC 2264 .” 1981. Web. 08 Mar 2021.

Vancouver:

Adams MT. AN OBSERVATIONAL STUDY OF LOW-MASS STAR FORMATION IN NGC 2264 . [Internet] [Doctoral dissertation]. University of Arizona; 1981. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10150/282033.

Council of Science Editors:

Adams MT. AN OBSERVATIONAL STUDY OF LOW-MASS STAR FORMATION IN NGC 2264 . [Doctoral Dissertation]. University of Arizona; 1981. Available from: http://hdl.handle.net/10150/282033

Vilnius University

4. Puzeras, Eduardas. Evoliuciniai cheminės sudėties pokyčiai helį centre deginančių žvaigždžių atmosferose.

Degree: PhD, Physics, 2011, Vilnius University

URL: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110809-17295 ;

►

Šiuolaikiniai astronominiai stebėjimai leidžia įtarti, kad „standartinis“ žvaigždžių evoliucijos modelis yra nepilnas ir turi būti patikslintas, įvedant „papildomą“ maišymąsi. Disertacija yra skirta Galaktikos raudonosios sankaupos… (more)

▼

Šiuolaikiniai astronominiai stebėjimai leidžia įtarti, kad „standartinis“ žvaigždžių evoliucijos modelis yra nepilnas ir turi būti patikslintas, įvedant „papildomą“ maišymąsi. Disertacija yra skirta Galaktikos raudonosios sankaupos žvaigždžių cheminės sudėties tyrimui ir maišymosi procesų sukeltų cheminės sudėties pokyčių mažos masės žvaigždžių atmosferose tyrimui bei papildomo maišymosi teorinių modelių įvertinimui. Tam tikslui buvo gauti ir ištirti 62-jų Galaktikos raudonosios sankaupos žvaigždžių ir 9 padrikojo spiečiaus NGC 7789 žvaigždžių didelės skiriamosios gebos spektrai, nustatyti žvaigždžių pagrindiniai parametrai ir cheminė sudėtis. Tyrimas patvirtino hipotezę, kad Galaktikos sankaupos žvaigždės yra santykinai jauni Saulės metalingumo objektai, susiformavę per pastaruosius keletą milijardų metų. Tirtose žvaigždėse buvo įvertintos maišymosi procesų pasekmėje pasikeitusių anglies ir azoto gausų vertės. Pademonstruota, kad sankaupos žvaigždės gali būti išskirtos į skirtingas evoliucines grupes pagal 12C/13C kriterijų. Nustatyta, kad anglies izotopų santykių vertes Galaktikos sankaupos žvaigždžių atmosferose gerai aprašo šaltojo žemutinių sluoksnių papildomo maišymosi modelis, tuo tarpu termohalinio papildomo maišymosi modelis turi būti papildytas, kad sutaptų su visais stebėjimų rezultatais. Nustatyta, kad anglies izotopų santykiai spiečiaus žvaigždėse yra labiau paveikti maišymosi procesų nei numato dabartiniai teoriniai žvaigždžių evoliucijos modeliai.

Modern observations provide evidences that the ‘standard’ stellar evolution model is incomplete and should take into account ‘extra’-mixing processes. This dissertation is dedicated to an observational study of the Galactic red clump as well as to investigations of evolutionary effects in atmospheres of low-mass helium-core burning stars and evaluation of theoretical models of extra-mixing processes in interiors of stars. For this purpose, the high-resolution spectra of 62 Galactic red clump stars and 9 evolved stars of the old open cluster NGC 7789 have been analysed and the main atmospheric parameters and chemical compositions were determined. The investigation confirmed the hypothesis that clump stars of the Galaxy are relatively young objects, reflecting mainly the near–solar metallicities developed in the local disk during the last few billion years of its history. Mixing induced carbon and nitrogen abundance modifications in the Galactic clump stars were investigated. The clump stars can be divided into distinct evolutionary groups using the 12C/13C criterion. The carbon isotope ratios of the Galactic clump stars are consistent with the Cool Bottom Processing (CBP) extra-mixing model; the Thermohaline extra-mixing model needs to be complemented in order to agree with observational data. The carbon isotope ratios in the NGC 7789 stars indicate a larger extra–mixing than it is foreseen by theoretical models.

Advisors/Committee Members: Zdanavičius, Kazimieras (Doctoral dissertation committee chair), Kamuntavičius, Gintautas (Doctoral dissertation committee member), Lazauskaitė, Romualda (Doctoral dissertation committee member), Straižys, Vytautas (Doctoral dissertation committee member), Tornau, Evaldas (Doctoral dissertation committee member), Bartkevičius, Antanas (Doctoral dissertation opponent), Mishenina, Tamara (Doctoral dissertation opponent).

Subjects/Keywords: Žvaigždės; Žvaigždžių cheminė sudėtis; Žvaigždžių evoliucija; Stars; Abundances-stars; Evolution-stars

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Puzeras, Eduardas. (2011). Evoliuciniai cheminės sudėties pokyčiai helį centre deginančių žvaigždžių atmosferose. (Doctoral Dissertation). Vilnius University. Retrieved from http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110809-17295 ;

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Chicago Manual of Style (16^th Edition):

Puzeras, Eduardas. “Evoliuciniai cheminės sudėties pokyčiai helį centre deginančių žvaigždžių atmosferose.” 2011. Doctoral Dissertation, Vilnius University. Accessed March 08, 2021. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110809-17295 ;.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

MLA Handbook (7^th Edition):

Puzeras, Eduardas. “Evoliuciniai cheminės sudėties pokyčiai helį centre deginančių žvaigždžių atmosferose.” 2011. Web. 08 Mar 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

Puzeras, Eduardas. Evoliuciniai cheminės sudėties pokyčiai helį centre deginančių žvaigždžių atmosferose. [Internet] [Doctoral dissertation]. Vilnius University; 2011. [cited 2021 Mar 08]. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110809-17295 ;.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Council of Science Editors:

Puzeras, Eduardas. Evoliuciniai cheminės sudėties pokyčiai helį centre deginančių žvaigždžių atmosferose. [Doctoral Dissertation]. Vilnius University; 2011. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110809-17295 ;

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vilnius University

5. Puzeras, Eduardas. Evolutionary effects in helium core burning star atmospheres.

Degree: Dissertation, Physics, 2011, Vilnius University

URL: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110919-19082 ;

►

Modern observations provide evidences that the ‘standard’ stellar evolution model is incomplete and should take into account ‘extra’-mixing processes. This dissertation is dedicated to an… (more)

▼

Modern observations provide evidences that the ‘standard’ stellar evolution model is incomplete and should take into account ‘extra’-mixing processes. This dissertation is dedicated to an observational study of the Galactic red clump as well as to investigations of evolutionary effects in atmospheres of low-mass helium-core burning stars and evaluation of theoretical models of extra-mixing processes in interiors of stars. For this purpose, the high-resolution spectra of 62 Galactic red clump stars and 9 evolved stars of the old open cluster NGC 7789 have been analysed and the main atmospheric parameters and chemical compositions were determined. The investigation confirmed the hypothesis that clump stars of the Galaxy are relatively young objects, reflecting mainly the near–solar metallicities developed in the local disk during the last few billion years of its history. Mixing induced carbon and nitrogen abundance modifications in the Galactic clump stars were investigated. The clump stars can be divided into distinct evolutionary groups using the 12C/13C criterion. The carbon isotope ratios of the Galactic clump stars are consistent with the Cool Bottom Processing (CBP) extra-mixing model; the Thermohaline extra-mixing model needs to be complemented in order to agree with observational data. The carbon isotope ratios in the NGC 7789 stars indicate a larger extra–mixing than it is foreseen by theoretical models.

Šiuolaikiniai astronominiai stebėjimai leidžia įtarti, kad „standartinis“ žvaigždžių evoliucijos modelis yra nepilnas ir turi būti patikslintas, įvedant „papildomą“ maišymąsi. Disertacija yra skirta Galaktikos raudonosios sankaupos žvaigždžių cheminės sudėties tyrimui ir maišymosi procesų sukeltų cheminės sudėties pokyčių mažos masės žvaigždžių atmosferose tyrimui bei papildomo maišymosi teorinių modelių įvertinimui. Tam tikslui buvo gauti ir ištirti 62-jų Galaktikos raudonosios sankaupos žvaigždžių ir 9 padrikojo spiečiaus NGC 7789 žvaigždžių didelės skiriamosios gebos spektrai, nustatyti žvaigždžių pagrindiniai parametrai ir cheminė sudėtis. Tyrimas patvirtino hipotezę, kad Galaktikos sankaupos žvaigždės yra santykinai jauni Saulės metalingumo objektai, susiformavę per pastaruosius keletą milijardų metų. Tirtose žvaigždėse buvo įvertintos maišymosi procesų pasekmėje pasikeitusių anglies ir azoto gausų vertės. Pademonstruota, kad sankaupos žvaigždės gali būti išskirtos į skirtingas evoliucines grupes pagal 12C/13C kriterijų. Nustatyta, kad anglies izotopų santykių vertes Galaktikos sankaupos žvaigždžių atmosferose gerai aprašo šaltojo žemutinių sluoksnių papildomo maišymosi modelis, tuo tarpu termohalinio papildomo maišymosi modelis turi būti papildytas, kad sutaptų su visais stebėjimų rezultatais. Nustatyta, kad anglies izotopų santykiai spiečiaus žvaigždėse yra labiau paveikti maišymosi procesų nei numato dabartiniai teoriniai žvaigždžių evoliucijos modeliai.

Advisors/Committee Members: Zdanavičius, Kazimieras (Doctoral dissertation committee chair), Kamuntavičius, Gintautas (Doctoral dissertation committee member), Lazauskaitė, Romualda (Doctoral dissertation committee member), Straižys, Vytautas (Doctoral dissertation committee member), Tornau, Evaldas (Doctoral dissertation committee member), Bartkevičius, Antanas (Doctoral dissertation opponent), Mishenina, Tamara (Doctoral dissertation opponent).

Subjects/Keywords: Stars; Abundances-stars; Evolution-stars; Žvaigždės; Žvaigždžių cheminė sudėtis; Žvaigždžių evoliucija

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Puzeras, Eduardas. (2011). Evolutionary effects in helium core burning star atmospheres. (Doctoral Dissertation). Vilnius University. Retrieved from http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110919-19082 ;

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Chicago Manual of Style (16^th Edition):

Puzeras, Eduardas. “Evolutionary effects in helium core burning star atmospheres.” 2011. Doctoral Dissertation, Vilnius University. Accessed March 08, 2021. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110919-19082 ;.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

MLA Handbook (7^th Edition):

Puzeras, Eduardas. “Evolutionary effects in helium core burning star atmospheres.” 2011. Web. 08 Mar 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

Puzeras, Eduardas. Evolutionary effects in helium core burning star atmospheres. [Internet] [Doctoral dissertation]. Vilnius University; 2011. [cited 2021 Mar 08]. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110919-19082 ;.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Council of Science Editors:

Puzeras, Eduardas. Evolutionary effects in helium core burning star atmospheres. [Doctoral Dissertation]. Vilnius University; 2011. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_110919-19082 ;

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Columbia University

6. Andrews, Jeffrey. Double White Dwarfs as Probes of Single and Binary Star Evolution.

Degree: 2016, Columbia University

URL: https://doi.org/10.7916/D8VH5NQ4

► As the endpoints of stars less massive than roughly eight solar masses, the population of Galactic white dwarfs (WD) contain information about complex stellar evolution… (more)

▼ As the endpoints of stars less massive than roughly eight solar masses, the population of Galactic white dwarfs (WD) contain information about complex stellar evolution processes. Associated pairs of WDs add an extra degree of leverage; both WDs must have formed and evolved together. The work presented in this dissertation uses various populations of double WDs (DWD) to constrain evolution of both single and binary stars. One example is the set of low-mass WDs with unseen WD companions, which are formed through a dynamically-unstable mass loss process called the common envelope. To work toward a quantitative understanding of the common envelope, we develop and apply a Bayesian statistical technique to identify the masses of the unseen WD companions. We provide results which can be compared to evolutionary models and hence a deeper understanding of how binary stars evolve through a common envelope. The statistical technique we develop can be applied to any population of single-line spectroscopic binaries. Binaries widely separated enough that they avoid any significant interaction independently evolve into separate WDs that can be identified in photometric and astrometric surveys. We discuss techniques for finding these objects, known as wide DWDs. We present a catalog of 142 candidate wide DWDs, combining both previously detected systems and systems we identify in our searches in the Sloan Digital Sky Survey. Having been born at the same time, the masses and cooling ages of the WDs in wide DWDs, obtained with our spectroscopic follow-up campaign can be used to constrain the initial-final mass relation, which relates a main sequence star to the mass of the WD into which it will evolve. We develop a novel Bayesian technique to interpret our data and present our resulting constraints on this relation which are particularly strong for initial masses between two and four solar masses. During this process, we identified one wide DWD, HS 2220+2146, that was peculiar since the more massive WD in this system evolved second. We construct an evolutionary formation scenario in which the system began as a hierarchical triple in which the inner binary merged (possibly due to Kozai-Lidov oscillations) forming a post-blue straggler binary. The system then evolved into the DWD we observe today. We further discuss the potential for identifying more wide DWDs, including peculiar systems like HS 2220+2146, in future surveys such as Gaia.

Subjects/Keywords: White dwarf stars; Binary stars; Stars – Evolution; Astronomy; Astrophysics

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Andrews, J. (2016). Double White Dwarfs as Probes of Single and Binary Star Evolution. (Doctoral Dissertation). Columbia University. Retrieved from https://doi.org/10.7916/D8VH5NQ4

Chicago Manual of Style (16^th Edition):

Andrews, Jeffrey. “Double White Dwarfs as Probes of Single and Binary Star Evolution.” 2016. Doctoral Dissertation, Columbia University. Accessed March 08, 2021. https://doi.org/10.7916/D8VH5NQ4.

MLA Handbook (7^th Edition):

Andrews, Jeffrey. “Double White Dwarfs as Probes of Single and Binary Star Evolution.” 2016. Web. 08 Mar 2021.

Vancouver:

Andrews J. Double White Dwarfs as Probes of Single and Binary Star Evolution. [Internet] [Doctoral dissertation]. Columbia University; 2016. [cited 2021 Mar 08]. Available from: https://doi.org/10.7916/D8VH5NQ4.

Council of Science Editors:

Andrews J. Double White Dwarfs as Probes of Single and Binary Star Evolution. [Doctoral Dissertation]. Columbia University; 2016. Available from: https://doi.org/10.7916/D8VH5NQ4

Michigan State University

7. Crosby, Brian David. Semi-analytic modeling of stellar populations in astrophysical simulations.

Degree: 2016, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:4360

►

Thesis Ph. D. Michigan State University. Astrophysics and Astronomy 2016

Understanding galaxy formation is an enduring questions in astrophysics. Galaxies are systems rich in interesting… (more)

▼

Thesis Ph. D. Michigan State University. Astrophysics and Astronomy 2016

Understanding galaxy formation is an enduring questions in astrophysics. Galaxies are systems rich in interesting physical processes, and the vast range of times and environments in which galaxies form and evolve offer a wealth of challenges. One of the primary driving forces in galaxies is the interaction of stellar populations with their surroundings. The nature of this interaction drives the evolution of both components, and the resulting behavior has a profound impact on the observable universe. In this dissertation I discuss the results of modeling this interaction in a variety of contexts using semi-analytic methods in conjunction with high-performance numerical simulations to bridge the huge dynamic ranges spanned by these processes. With these techniques I explore the environments in which Population III stars form, studying the transition to chemically-enriched star formation, and quantifying the changing environment and assembly history of the dark matter halos which host Population III stars in a universe of increasingly chemical complexity. Chemical enrichment in high redshift proto-galaxies is investigated by coupling semi-analytic models of star formation and feedback to cosmological N-body simulations. The resulting elemental abundance ratios are compared to those observed in metal-poor stars and satellite systems of the Milky Way, with the comparison constraining the nature of Population III stars, galaxy formation at high redshift, and the transition from metal-free to chemically enriched star formation. Ensembles of semi-analytic models representing internal galactic processes are used to develop a new formalism for representing galaxies in cosmological simulations of galaxy clusters. This method is used to investigate galaxy formation in a cluster environment and the interaction between cluster galaxies and the intracluster medium. The interaction between stellar populations in disk galaxies and the diffuse circumgalactic medium is studied in simulations of idealized disk galaxies. The interplay of stellar feedback and the development of multiphase gas in the circumgalactic medium, and in turn the influence of this multiphase gas falling back onto the stellar disk is investigated.

Description based on online resource;

Advisors/Committee Members: O'Shea, Brian W, Donahue, Megan, Voit, Mark, Chivukula, Sekhar, Linnemann, Jim.

Subjects/Keywords: Stars – Populations – Simulation methods; Stars – Evolution; Galaxies – Evolution; Astrophysics

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Crosby, B. D. (2016). Semi-analytic modeling of stellar populations in astrophysical simulations. (Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:4360

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Crosby, Brian David. “Semi-analytic modeling of stellar populations in astrophysical simulations.” 2016. Thesis, Michigan State University. Accessed March 08, 2021. http://etd.lib.msu.edu/islandora/object/etd:4360.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Crosby, Brian David. “Semi-analytic modeling of stellar populations in astrophysical simulations.” 2016. Web. 08 Mar 2021.

Vancouver:

Crosby BD. Semi-analytic modeling of stellar populations in astrophysical simulations. [Internet] [Thesis]. Michigan State University; 2016. [cited 2021 Mar 08]. Available from: http://etd.lib.msu.edu/islandora/object/etd:4360.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Crosby BD. Semi-analytic modeling of stellar populations in astrophysical simulations. [Thesis]. Michigan State University; 2016. Available from: http://etd.lib.msu.edu/islandora/object/etd:4360

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universiteit Utrecht

8. Bonačić Marinović, A.A. Nucleosynthesis and evolution of AGB stars in binary systems.

Degree: 2007, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/23521

► Thermally-pulsating asymptotic giant branch (TP-AGB) stars are hundreds of times larger and several tens of thousand times more luminous than than the Sun. They are… (more)

▼ Thermally-pulsating asymptotic giant branch (TP-AGB) stars are hundreds of times larger and several tens of thousand times more luminous than than the Sun. They are composed of a compact carbon and oxygen core and an extended hydrogen convective envelope. These stars are intermediate-mass objects in their last stages of evolution, just before they die as a cooling compact star called a white dwarf. TP-AGB stars are the main producers of slow neutron capture (s-) process elements, which are elements heavier than iron such as strontium, yttrium, zirconium, caesium, barium, lanthanum and cerium. There are still large uncertainties associated with the formation of the main neutron source needed for the synthesis of these elements and with the physics of these stars in general. Observations of s-process element enhancements in stars can be used as constraints on theoretical models. For the first time we apply stellar population synthesis to the problem of s-process nucleosynthesis in TP-AGB stars and have constrained the free parameters describing the physics of the mixing process of these elements into the stellar envelope and the properties of the neutron source. We show that the amount of 13C which effectively contributes as a neutron source to s-process element synthesis tends to decrease with metallicity and that it is constrained to a narrower range of values than that previously believed. We also find that the mixing of s-process elements into the stellar envelope happens in stars of lower initial mass than those predicted by theoretical models. Binary systems which contained a TP-AGB star, now observed as a white dwarf, show significant orbital eccentricity. However, the strong tidal interaction which should have taken place due to the large size of a TP-AGB star must have dissipated significant amounts of energy and consequently circularised the orbit. This indicates that a mechanism which enhances the orbital eccentricity must take place in order to explain the observations. We propose a model for TP-AGB stars in binary systems in which their mass-loss is enhanced when the system components are closer to each other. This uneven mass-loss along the orbit provides a mechanism which enhances the orbital eccentricity in such a way that it competes with the tidal circularisation. We show that by applying this mechanism it is possible to explain the eccentric orbit of systems such as Sirius and of many barium stars, which so far had no explanation under the standard assumptions considering only tidal dissipation.

Subjects/Keywords: Natuur- en Sterrenkunde; stars: AGB and post-AGB; stars; abundances; nucleosynthesis; stars: binary; stars: evolution; stars: Sirius

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bonačić Marinović, A. A. (2007). Nucleosynthesis and evolution of AGB stars in binary systems. (Doctoral Dissertation). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/23521

Chicago Manual of Style (16^th Edition):

Bonačić Marinović, A A. “Nucleosynthesis and evolution of AGB stars in binary systems.” 2007. Doctoral Dissertation, Universiteit Utrecht. Accessed March 08, 2021. http://dspace.library.uu.nl:8080/handle/1874/23521.

MLA Handbook (7^th Edition):

Bonačić Marinović, A A. “Nucleosynthesis and evolution of AGB stars in binary systems.” 2007. Web. 08 Mar 2021.

Vancouver:

Bonačić Marinović AA. Nucleosynthesis and evolution of AGB stars in binary systems. [Internet] [Doctoral dissertation]. Universiteit Utrecht; 2007. [cited 2021 Mar 08]. Available from: http://dspace.library.uu.nl:8080/handle/1874/23521.

Council of Science Editors:

Bonačić Marinović AA. Nucleosynthesis and evolution of AGB stars in binary systems. [Doctoral Dissertation]. Universiteit Utrecht; 2007. Available from: http://dspace.library.uu.nl:8080/handle/1874/23521

9. BYRNE, CONOR MICHAEL. Atomic Diffusion and Pulsation in Post-Common-Envelope Binary Stars.

Degree: School of Physics. Discipline of Physics, 2020, Trinity College Dublin

URL: http://hdl.handle.net/2262/92683

► I study the evolution of peculiar low-mass, evolved stars. Two groups of interest are the core-helium-burning hot subdwarfs and the shell-hydrogen-burning low-mass pre-white dwarfs. Stars… (more)

▼ I study the evolution of peculiar low-mass, evolved stars. Two groups of interest are the core-helium-burning hot subdwarfs and the shell-hydrogen-burning low-mass pre-white dwarfs. Stars in both groups have had previous interactions with a companion in order to remove most of their outer layers to leave the stars we see today. A detailed understanding of the past evolution of these stars provides important information about the interaction between close binary companions. This in itself is important, as approximately half of all stars in the Milky Way are in a binary or multiple star system. Additionally, hot subdwarfs show a variety of unusual surface compositions, with some stars showing lead and zirconium on their surface in amounts thousands of times more plentiful than seen in the Sun. It has been proposed that this is the result of radiative levitation, whereby outgoing radiation from the star can provide an upward force on certain elements, depending on their atomic structure. The open-source MESA stellar evolution code was used to compute models of hot subdwarf stars and low-mass white dwarfs. These models were produced by using a large mass-loss rate to strip the outer layers from a red giant model, leaving either a low-mass core-helium burning model (subdwarf) or a model with an inert helium core and a thin hydrogen-burning envelope (pre-white dwarf) depending on the mass of the red giant core. Models were produced both with and without the effects of radiative levitation to determine the impact that this has on the evolution and surface composition of these stars. These were the first self-consistent models of hot subdwarfs from Main Sequence star through to the Horizontal Branch. It is shown that radiative levitation is important in the phase of evolution immediately following the ejection of the common envelope, something which had not previously been considered. Comparison with the abundances of the observed population of hot subdwarfs showed that while the qualitative abundance patterns agree, the efficiency of radiative levitation is too strong in the simulations. This implies that other mixing processes must be invoked in order to accurately reproduce the observed abundances. In the case of heavy metals such as lead and zirconium, the amount of atomic data presently available is insufficient to calculate radiative accelerations for these elements. In the case of the low-mass white dwarfs, the interest here focused on the discovery by Pietrukowicz et al. (2017) and Kupfer et al. (2019) of large-amplitude pulsating variable stars which show surface temperatures similar to hot subdwarfs. These stars are currently known as Blue Large-Amplitude Pulsators (BLAPs). The proposed structure of these stars is a low-mass pre-white dwarf, formed in a similar manner to a hot subdwarf. I used the GYRE stellar oscillation code to analyse the structure of my models and determined that low-mass pre-white dwarfs can pulsate when they have a temperature and surface gravity equivalent to the observed pulsators, with… Advisors/Committee Members: Bradley, Louise.

Subjects/Keywords: subdwarfs; white dwarfs; stars evolution; diffusion; stars horizontal branch; stars oscillations; atomic processes; stars chemically peculiar; stars abundances

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

BYRNE, C. M. (2020). Atomic Diffusion and Pulsation in Post-Common-Envelope Binary Stars. (Thesis). Trinity College Dublin. Retrieved from http://hdl.handle.net/2262/92683

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

BYRNE, CONOR MICHAEL. “Atomic Diffusion and Pulsation in Post-Common-Envelope Binary Stars.” 2020. Thesis, Trinity College Dublin. Accessed March 08, 2021. http://hdl.handle.net/2262/92683.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

BYRNE, CONOR MICHAEL. “Atomic Diffusion and Pulsation in Post-Common-Envelope Binary Stars.” 2020. Web. 08 Mar 2021.

Vancouver:

BYRNE CM. Atomic Diffusion and Pulsation in Post-Common-Envelope Binary Stars. [Internet] [Thesis]. Trinity College Dublin; 2020. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2262/92683.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

BYRNE CM. Atomic Diffusion and Pulsation in Post-Common-Envelope Binary Stars. [Thesis]. Trinity College Dublin; 2020. Available from: http://hdl.handle.net/2262/92683

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Hawaii – Manoa

10. Dahm, Scott E. The evolution of young clusters.

Degree: PhD, 2009, University of Hawaii – Manoa

URL: http://hdl.handle.net/10125/12105

Electronic reproduction.

Also available by subscription via World Wide Web

xvii, 261 leaves, bound ill. (some col.) 29 cm

Subjects/Keywords: Stars – Clusters; Stars – Evolution; Stars – Formation

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dahm, S. E. (2009). The evolution of young clusters. (Doctoral Dissertation). University of Hawaii – Manoa. Retrieved from http://hdl.handle.net/10125/12105

Chicago Manual of Style (16^th Edition):

Dahm, Scott E. “The evolution of young clusters.” 2009. Doctoral Dissertation, University of Hawaii – Manoa. Accessed March 08, 2021. http://hdl.handle.net/10125/12105.

MLA Handbook (7^th Edition):

Dahm, Scott E. “The evolution of young clusters.” 2009. Web. 08 Mar 2021.

Vancouver:

Dahm SE. The evolution of young clusters. [Internet] [Doctoral dissertation]. University of Hawaii – Manoa; 2009. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10125/12105.

Council of Science Editors:

Dahm SE. The evolution of young clusters. [Doctoral Dissertation]. University of Hawaii – Manoa; 2009. Available from: http://hdl.handle.net/10125/12105

11. Weston, Simon. Post asymptotic giant branch and central stars of planetary nebulae in the Galactic halo.

Degree: PhD, 2012, University of Hertfordshire

URL: http://hdl.handle.net/2299/9042

► Post asymptotic giant branch (post-AGB) stars, central stars of planetary nebulae (CSPNe) and planetary nebulae (PNe) are important phases of stellar evolution as the material… (more)

▼ Post asymptotic giant branch (post-AGB) stars, central stars of planetary nebulae (CSPNe) and planetary nebulae (PNe) are important phases of stellar evolution as the material they feedback is the seed of subsequent star formation in a galaxy. The majority of low and intermediate mass stars are expected to evolve through these channels, however, it is uncertain how many actually do, and at what rate. The Galactic halo, with its older population, provides a direct test of evolutionary models for low mass stars. Birthrate estimates of PNe are uncertain and worse still, are in contradiction with accepted white dwarf (WD) birthrate estimates. Much of the uncertainty stems from the lack of complete samples and poorly determined distance estimates. New surveys such as the Sloan Digital Sky Survey (SDSS), Galaxy Evolutionary Ex- plorer (GALEX) and the INT Photometric H® Survey (IPHAS) have discovered many new PNe and have observed the far edges of the Galaxy. Improved methods of determining distances to CSPNe are presented here, using model atmospheres, evolutionary tracks and high resolution reddening maps utilising these revolution- ary surveys. Locating the CSPN is non-trivial particularly for evolved PNe, as they are ex- tended with their central star often displaced from the centre of the nebula. There- fore, photometric criteria are required to locate the CSPN in the nebula’s field. Synthetic photometry of the CSPNe is derived from spectral energy distributions (SEDs) computed from a grid of model atmospheres covering the parameter range of CSPNe. The SEDs are convolved with filter transmission curves to compute synthetic magnitudes for a given photometric system which are then calibrated with standard stars and WDs. A further project borne out of a search for luminous central stars of faint PNe, resulted in a systematic search for post-AGB stars in the Galactic halo. In this work, new candidate halo post-AGB stars are discovered from a search through the SDSS spectroscopic database. Combined with previously identified halo post- AGB stars, including the results of a sub-sample from the Palomar-Green (PG) survey, the number of observed and predicted populations are compared. The number of observed post-AGB candidates shows a remarkable deficit to expecta- tions. A survey within a subset of the photometric database of SDSS supports the findings of the PG and SDSS spectroscopic surveys. These findings provide strong evidence for a lack of post-AGB stars in the Galac- tic halo and thick disc. A plausible explanation is that a large fraction of stars in these old, metal-poor populations are evolving via alternative channels. The implications of such a result are far reaching with knock on effects for stellar evolutionary theory, galactic evolution and extragalactic redshift estimates.

Subjects/Keywords: 523.8; stars: evolution; stars: AGB and post-AGB; Galaxy: halo

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Weston, S. (2012). Post asymptotic giant branch and central stars of planetary nebulae in the Galactic halo. (Doctoral Dissertation). University of Hertfordshire. Retrieved from http://hdl.handle.net/2299/9042

Chicago Manual of Style (16^th Edition):

Weston, Simon. “Post asymptotic giant branch and central stars of planetary nebulae in the Galactic halo.” 2012. Doctoral Dissertation, University of Hertfordshire. Accessed March 08, 2021. http://hdl.handle.net/2299/9042.

MLA Handbook (7^th Edition):

Weston, Simon. “Post asymptotic giant branch and central stars of planetary nebulae in the Galactic halo.” 2012. Web. 08 Mar 2021.

Vancouver:

Weston S. Post asymptotic giant branch and central stars of planetary nebulae in the Galactic halo. [Internet] [Doctoral dissertation]. University of Hertfordshire; 2012. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2299/9042.

Council of Science Editors:

Weston S. Post asymptotic giant branch and central stars of planetary nebulae in the Galactic halo. [Doctoral Dissertation]. University of Hertfordshire; 2012. Available from: http://hdl.handle.net/2299/9042

University of Minnesota

12. Grammer, Skyler. The massive Star Population in M101.

Degree: PhD, 2014, University of Minnesota

URL: http://hdl.handle.net/11299/167865

► An increasing number of non-terminal giant eruptions are being observed by modern supernova and transient surveys. Very little is known about the origin of these… (more)

▼ An increasing number of non-terminal giant eruptions are being observed by modern supernova and transient surveys. Very little is known about the origin of these giant eruptions and their progenitors which are presumably very-massive, evolved stars such as luminous blue variables, hypergiants, and supergiants. Motivated by the small number of progenitors positively associated with these giant eruptions, we have begun a survey of the luminous and evolved massive star populations in several nearby galaxies. We aim to identify the likely progenitors of the giant eruptions, study the spatial variations in the stellar populations, and examine the relationship between massive star populations and their environment.The work presented here is focused on stellar populations in the relatively nearby, giant, spiral galaxy M101 from sixteen archival BVI HST/ACS images. We create a catalog of stars in the direction to M101 with photometric errors < 10% for V < 24.5 and 50% completeness down to V = 26.5 even in regions of high stellar crowding. Using color and magnitude criteria we have identified candidate luminous OB type stars and blue supergiants, yellow supergiants, and red supergiants for future observation. We examine their spatial distributions across the face of M101 and find that the ratio of blue to red supergiants decreases by two orders of magnitude over the radial extent.From our catalog, we derive the the star formation history (SFH) for the stellar populations in five 2' wide annuli by fitting the color-magnitude diagrams. Binning the SFH into time frames corresponding to populations traced by Halpha, far ultraviolet (FUV), and near ultraviolet (NUV) emission, we show that the fraction of stellar populations young enough to contribute in Halpha is 15% " 35% in the inner regions, compared to less than 5% in the outer regions. This provides a sufficient explanation for the lack of Halpha emission at large radii. We also model the blue to red supergiant ratio in our five annuli, examine the effects that a metallicity gradient and variable SFH have on the predicted ratios, and compare to the observed values. We find that the radial behavior of our modeled blue to red supergiant ratios is highly sensitive to both spatial variations in the SFH and metallicity. Incorporating the derived SFH into the modeled ratios, we are able to reproduce the observed values at large radii (low metallicity), but at small radii (high metallicity) the modeled and observed ratios are discrepant. Though photometry has proven to be a powerful tool to identify candidate evolved massive stars and their effects on their host galaxy, spectroscopy is necessary to study the physical properties of individual stars. We observed moderate-resolution optical spectra for 56 of the brightest stars in the direction to M101 using the Multiple Mirror Telescope. We also created light curves for each target using multi-epoch UBV R images from the Large Binocular Telescope. We separate the spectroscopially confirmed members of M101 into four groups: hot…

Subjects/Keywords: Galaxies; Massive Stars; Stellar evolution; Astrophysics

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Grammer, S. (2014). The massive Star Population in M101. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/167865

Chicago Manual of Style (16^th Edition):

Grammer, Skyler. “The massive Star Population in M101.” 2014. Doctoral Dissertation, University of Minnesota. Accessed March 08, 2021. http://hdl.handle.net/11299/167865.

MLA Handbook (7^th Edition):

Grammer, Skyler. “The massive Star Population in M101.” 2014. Web. 08 Mar 2021.

Vancouver:

Grammer S. The massive Star Population in M101. [Internet] [Doctoral dissertation]. University of Minnesota; 2014. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/11299/167865.

Council of Science Editors:

Grammer S. The massive Star Population in M101. [Doctoral Dissertation]. University of Minnesota; 2014. Available from: http://hdl.handle.net/11299/167865

University of Arizona

13. Vrba, Frederick John, 1949-. THE MAGNETIC FIELD STRUCTURE AND EMBEDDED STELLAR POPULATION OF DARK CLOUD COMPLEXES .

Degree: 1976, University of Arizona

URL: http://hdl.handle.net/10150/289404

Subjects/Keywords: Nebulae.; Stars – Evolution.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Vrba, Frederick John, 1. (1976). THE MAGNETIC FIELD STRUCTURE AND EMBEDDED STELLAR POPULATION OF DARK CLOUD COMPLEXES . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/289404

Chicago Manual of Style (16^th Edition):

Vrba, Frederick John, 1949-. “THE MAGNETIC FIELD STRUCTURE AND EMBEDDED STELLAR POPULATION OF DARK CLOUD COMPLEXES .” 1976. Doctoral Dissertation, University of Arizona. Accessed March 08, 2021. http://hdl.handle.net/10150/289404.

MLA Handbook (7^th Edition):

Vrba, Frederick John, 1949-. “THE MAGNETIC FIELD STRUCTURE AND EMBEDDED STELLAR POPULATION OF DARK CLOUD COMPLEXES .” 1976. Web. 08 Mar 2021.

Vancouver:

Vrba, Frederick John 1. THE MAGNETIC FIELD STRUCTURE AND EMBEDDED STELLAR POPULATION OF DARK CLOUD COMPLEXES . [Internet] [Doctoral dissertation]. University of Arizona; 1976. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10150/289404.

Council of Science Editors:

Vrba, Frederick John 1. THE MAGNETIC FIELD STRUCTURE AND EMBEDDED STELLAR POPULATION OF DARK CLOUD COMPLEXES . [Doctoral Dissertation]. University of Arizona; 1976. Available from: http://hdl.handle.net/10150/289404

University of Arizona

14. Jensen, Eric Bruce, 1948-. THE NATURE OF HEAVY-ELEMENT ABUNDANCE GRADIENTS IN GALAXIES .

Degree: 1977, University of Arizona

URL: http://hdl.handle.net/10150/289539

Subjects/Keywords: Stars – Evolution.; Galaxies.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jensen, Eric Bruce, 1. (1977). THE NATURE OF HEAVY-ELEMENT ABUNDANCE GRADIENTS IN GALAXIES . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/289539

Chicago Manual of Style (16^th Edition):

Jensen, Eric Bruce, 1948-. “THE NATURE OF HEAVY-ELEMENT ABUNDANCE GRADIENTS IN GALAXIES .” 1977. Doctoral Dissertation, University of Arizona. Accessed March 08, 2021. http://hdl.handle.net/10150/289539.

MLA Handbook (7^th Edition):

Jensen, Eric Bruce, 1948-. “THE NATURE OF HEAVY-ELEMENT ABUNDANCE GRADIENTS IN GALAXIES .” 1977. Web. 08 Mar 2021.

Vancouver:

Jensen, Eric Bruce 1. THE NATURE OF HEAVY-ELEMENT ABUNDANCE GRADIENTS IN GALAXIES . [Internet] [Doctoral dissertation]. University of Arizona; 1977. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10150/289539.

Council of Science Editors:

Jensen, Eric Bruce 1. THE NATURE OF HEAVY-ELEMENT ABUNDANCE GRADIENTS IN GALAXIES . [Doctoral Dissertation]. University of Arizona; 1977. Available from: http://hdl.handle.net/10150/289539

University of Arizona

15. Lowenthal, James Daniel. Line emission from galaxies at high redshift.

Degree: 1991, University of Arizona

URL: http://hdl.handle.net/10150/185621

► The results of a multi-faceted search for spectral line emission from galaxies at high redshift are presented. Deep two-dimensional spectra of four blank sky fields… (more)

▼ The results of a multi-faceted search for spectral line emission from galaxies at high redshift are presented. Deep two-dimensional spectra of four blank sky fields were taken at the Multiple Mirror Telescope (MMT) at wavelengths corresponding to redshifted Lyα emission in the range 2.7 < z < 4.7, and the resulting non-detections are used to place upper limits on the space density of randomly distributed Lyα emitters. Although the predictions of a conservative model of galaxy formation incorporating cold dark matter are not excluded in a statistical sense, the search would have detected star-forming dwarf galaxies comparable to the Magellanic Clouds at z = 3, given minimal extinction by dust. The Goddard Fabry-Perot Imager, a piezo-electrically controlled tunable narrow-band filter system with a stand-alone CCD system, was developed and tested, and used at the Kitt Peak National Observatory (KPNO) 4 m telescope to image the damped Lyα absorbing clouds towards three high-redshift QSOs in the light of redshifted Lyα. A companion galaxy to one of the damped systems was discovered and confirmed with followup spectroscopy, and its properties are presented and discussed; the companion exhibits strong Lyα and weak C IV λ1549 and He II λ1640 emission lines, and is apparently producing stars at a rate SFR ∼ 5 - 10M(⊙) yr⁻¹. The implications of the companion's proximity to the damped cloud are analyzed in view of the previous non-detections, and a lower limit to the spatial correlation function of the damped Lyα systems with galaxies is given. Spectroscopic limits on Lyα emission from seven damped systems, including some known to have low chemical and dust abundances, imply low levels of star formation, SFR ≲ 1 M(⊙) yr⁻¹, but extinction by dust in some cases may cause an underestimation of these rates. With near-infrared spectrographs at the MMT and the KPNO 4 m, eight damped Lyα systems were searched for spectral lines characteristic of star formation regions but redshifted from the optical into the near-infrared. A possible detection of (O II) λ3727 and Hβ from one system implies a star formation rate on the order of 100 M(⊙) yr⁻¹, though the remainder of the observations produced non-detections compatible with the Lyα emission limits. The implications for galaxy formation and evolution at high redshift are discussed. Advisors/Committee Members: Green, Richard (advisor), Hogan, Craig (committeemember), Rieke, Marcia (committeemember).

Subjects/Keywords: Stars – Evolution; Galaxies.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lowenthal, J. D. (1991). Line emission from galaxies at high redshift. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/185621

Chicago Manual of Style (16^th Edition):

Lowenthal, James Daniel. “Line emission from galaxies at high redshift. ” 1991. Doctoral Dissertation, University of Arizona. Accessed March 08, 2021. http://hdl.handle.net/10150/185621.

MLA Handbook (7^th Edition):

Lowenthal, James Daniel. “Line emission from galaxies at high redshift. ” 1991. Web. 08 Mar 2021.

Vancouver:

Lowenthal JD. Line emission from galaxies at high redshift. [Internet] [Doctoral dissertation]. University of Arizona; 1991. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10150/185621.

Council of Science Editors:

Lowenthal JD. Line emission from galaxies at high redshift. [Doctoral Dissertation]. University of Arizona; 1991. Available from: http://hdl.handle.net/10150/185621

University of Victoria

16. Clarkson, Ondrea. The first stars and the convective-reactive regime.

Degree: Department of Physics and Astronomy, 2021, University of Victoria

URL: http://hdl.handle.net/1828/12548

► Due to their initially metal-free composition, the fi rst stars in the Universe, which are termed Population III (Pop III) stars, were fundamentally different than… (more)

▼ Due to their initially metal-free composition, the fi rst stars in the Universe, which are termed Population III (Pop III) stars, were fundamentally different than later generations of stars. As of now, we have yet to observe a truly metal-free star although much effort has been placed on this task and that of nding the second generation of stars. Given they were the first stars, Pop III stars are expected to have made the fi rst contributions to elements heavier than those produced during the Big Bang. For decades signi cant mixing between H and He burning layers has been reported in simulations of massive Pop III stars. In this thesis I investigate this poorly understood phenomenon and I posit that interactions between hydrogen and helium-burning layers in Pop III stars may have had a profound impact on their nucleosynthetic contribution to the early universe, and second generation of stars. First, I examined a single massive Pop III star. This was done using a combination of stellar evolution and single-zone nucleosynthesis calculations. For this project I investigated whether the abundances in the most iron-poor stars observed at the time of publication, were reproducible by an interaction between H and He-burning layers. Here it was found that the i process may operate under such conditions. The neutrons are able to ll in odd elements such as Na, creating what is sometimes called the `light-element abundance signature' in observed CEMP stars. I also present the finding that it is possible to produce elements heavier than iron as a result of the i process operating in massive Pop III stars. A parameter study I conducted on H-He interactions in a grid of 22/26 MESA stellar evolution simulations is then described. I grouped these interactions into four categories based on the core-contraction phase they occur in and the convective stability of the helium-burning layer involved. I also examine in detail the hydrogen burning conditions within massive Pop III stars and the behaviour of the CN cycle during H-He interactions. The latter is compared to observed CN ratios in CEMP stars. Finally, I describe the first ever 4pi 3D hydrodynamic simulations of H-He shells in Pop III stars. I also examine the challenges in modelling such con gurations and demonstrate the contributions I have made in modelling Pop III H and He shell systems in the PPMStar hydrodynamics code. My contributions apply to other stellar modelling applications as well. Advisors/Committee Members: Herwig, Falk (supervisor).

Subjects/Keywords: Stars; Population III; Stellar Evolution; Nucleosynthesis

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Clarkson, O. (2021). The first stars and the convective-reactive regime. (Thesis). University of Victoria. Retrieved from http://hdl.handle.net/1828/12548

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Clarkson, Ondrea. “The first stars and the convective-reactive regime.” 2021. Thesis, University of Victoria. Accessed March 08, 2021. http://hdl.handle.net/1828/12548.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Clarkson, Ondrea. “The first stars and the convective-reactive regime.” 2021. Web. 08 Mar 2021.

Vancouver:

Clarkson O. The first stars and the convective-reactive regime. [Internet] [Thesis]. University of Victoria; 2021. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/1828/12548.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Clarkson O. The first stars and the convective-reactive regime. [Thesis]. University of Victoria; 2021. Available from: http://hdl.handle.net/1828/12548

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

17. Matson, Rachel A. Fundamental Parameters of Eclipsing Binaries in the Kepler Field of View.

Degree: PhD, Physics and Astronomy, 2016, Georgia State University

URL: https://scholarworks.gsu.edu/phy_astr_diss/91

► Accurate knowledge of stellar parameters such as mass, radius, effective temperature, and composition inform our understanding of stellar evolution and constrain theoretical models. Binaries… (more)

▼ Accurate knowledge of stellar parameters such as mass, radius, effective temperature, and composition inform our understanding of stellar evolution and constrain theoretical models. Binaries and, in particular, eclipsing binaries make it possible to measure directly these parameters without reliance on models or scaling relations. In this dissertation we derive fundamental parameters of stars in close binary systems with and without (detected) tertiary companions to test and inform theories of stellar and binary evolution. A subsample of 41 detached and semi-detached short-period eclipsing binaries observed by NASA’s Kepler mission and analyzed for eclipse timing variations form the basis of our sample. Radial velocities and spectroscopic orbits for these systems are derived from moderate resolution optical spectra and used to determine individual masses for 34 double-lined spectroscopic binaries, five of which have detected tertiaries. The resulting mass ratio M₂/M₁ distribution is bimodal, dominated by binaries with like-mass pairs and semi-detached classical Algol systems that have undergone mass transfer. A more detailed analysis of KIC 5738698, a detached binary consisting of two F-type main sequence stars with an orbital period of 4.8 days, uses the derived radial velocities to reconstruct the primary and secondary component spectra via Doppler tomography and derive atmospheric parameters for both stars. These parameters are then combined with Kepler photometry to obtain accurate masses and radii through light curve and radial velocity fitting with the binary modeling software ELC. A similar analysis is performed for KOI-81, a rapidly-rotating B-type star orbited by a low-mass white dwarf, using UV spectroscopy to identify the hot companion and determine masses and temperatures of both components. Well defined stellar parameters for KOI-81 and the other close binary systems examined in this dissertation enable detailed analyses of the physical attributes of systems in different evolutionary stages, providing important constraints for the formation and evolution of close binary systems. Advisors/Committee Members: Douglas R. Gies, Todd J. Henry, Harold A. McAlister, Guillermo Torres, Russel J. White, Joshua S. Von Korff.

Subjects/Keywords: astronomy; binaries; binaries: eclipsing; binaries: spectroscopic; stars: fundamental parameters; stars: evolution; stars: individual (KIC 5738698); stars: individual (KOI-81)

8 more images…

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Matson, R. A. (2016). Fundamental Parameters of Eclipsing Binaries in the Kepler Field of View. (Doctoral Dissertation). Georgia State University. Retrieved from https://scholarworks.gsu.edu/phy_astr_diss/91

Chicago Manual of Style (16^th Edition):

Matson, Rachel A. “Fundamental Parameters of Eclipsing Binaries in the Kepler Field of View.” 2016. Doctoral Dissertation, Georgia State University. Accessed March 08, 2021. https://scholarworks.gsu.edu/phy_astr_diss/91.

MLA Handbook (7^th Edition):

Matson, Rachel A. “Fundamental Parameters of Eclipsing Binaries in the Kepler Field of View.” 2016. Web. 08 Mar 2021.

Vancouver:

Matson RA. Fundamental Parameters of Eclipsing Binaries in the Kepler Field of View. [Internet] [Doctoral dissertation]. Georgia State University; 2016. [cited 2021 Mar 08]. Available from: https://scholarworks.gsu.edu/phy_astr_diss/91.

Council of Science Editors:

Matson RA. Fundamental Parameters of Eclipsing Binaries in the Kepler Field of View. [Doctoral Dissertation]. Georgia State University; 2016. Available from: https://scholarworks.gsu.edu/phy_astr_diss/91

Columbia University

18. Emerick, Andrew James. Stellar Feedback and Chemical Evolution In Dwarf Galaxies.

Degree: 2019, Columbia University

URL: https://doi.org/10.7916/d8-29kz-8d92

► Motivated by the desire to investigate two of the largest outstanding problems in galactic evolution – stellar feedback and galactic chemical evolution – we develop… (more)

▼ Motivated by the desire to investigate two of the largest outstanding problems in galactic evolution – stellar feedback and galactic chemical evolution – we develop the first set of galaxy-scale simulations that simultaneously follow star formation with individual stars and their associated multi-channel stellar feedback and multi-element metal yields. We developed these simulations to probe the way in which stellar feedback, including stellar winds, stellar radiation, and supernovae, couples to the interstellar medium (ISM), regulates star formation, and drives outflows in dwarf galaxies. We follow the evolution of the individual metal yields associated with these stars in order to trace how metals mix within the ISM and are ejected into the circumgalactic and intergalactic media (CGM, IGM) through outflows. This study is directed with the ultimate goal of leveraging the ever increasing quality of stellar abundance measurements within our own Milky Way galaxy and in nearby dwarf galaxies to understand galactic evolution. Our simulations follow the evolution of an idealized, isolated, low mass dwarf galaxy (Mvir ∼ 10⁹ M ) for ∼ 500 Myr using the adaptive mesh refinement hydrodynamics code Enzo. We implemented a new star formation routine which deposits stars individually from 1 M to 100 M . Using tabulated stellar properties, we follow the stellar feedback from each star. For massive stars (M∗ > 8 M ) we follow their stellar winds, ionizing radiation (using an adaptive ray-tracing radiative transfer method), the FUV radiation which leads to photoelectric heating of dust grains, Lyman-Werner radiation, which leads to H2 dissociation, and core collapse supernovae. In addition, we follow the asymptotic giant branch (AGB) winds of low-mass stars (M∗ < 8 M ) and Type Ia supernovae. We investigate how this detailed model for stellar feedback drives the evolution of low mass galaxies. We find agreement with previous studies that these low mass dwarf galaxies exhibit bursty, irregular star formation histories with significant feedback-driven winds. Using these simulations, we investigate the role that stellar radiation feedback plays in the evolution of low mass dwarf galaxies. In this regime, we find that the local effects of stellar radiation (within ~ 10 pc of the massive, ionizing source star) act to regulate star formation by rapidly destroying cold, dense gas around newly formed stars. For the first time, we find that the long-range radiation effects far from the birth sites are vital for carving channels of diffuse gas in the ISM which dramatically increase the effect of supernovae. We find this effect is necessary to drive strong winds with significant mass loading factors and has a significant impact on the metal content of the ISM. Focusing on the evolution of individual metals within this galaxy, it remains an outstanding question as to what degree (if any) metal mixing processes in a multi-phase ISM influence observed stellar abundance patterns. To address this issue, we characterize the…

Subjects/Keywords: Astronomy; Astrophysics; Galaxies – Evolution; Molecular evolution; Stars – Formation

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Emerick, A. J. (2019). Stellar Feedback and Chemical Evolution In Dwarf Galaxies. (Doctoral Dissertation). Columbia University. Retrieved from https://doi.org/10.7916/d8-29kz-8d92

Chicago Manual of Style (16^th Edition):

Emerick, Andrew James. “Stellar Feedback and Chemical Evolution In Dwarf Galaxies.” 2019. Doctoral Dissertation, Columbia University. Accessed March 08, 2021. https://doi.org/10.7916/d8-29kz-8d92.

MLA Handbook (7^th Edition):

Emerick, Andrew James. “Stellar Feedback and Chemical Evolution In Dwarf Galaxies.” 2019. Web. 08 Mar 2021.

Vancouver:

Emerick AJ. Stellar Feedback and Chemical Evolution In Dwarf Galaxies. [Internet] [Doctoral dissertation]. Columbia University; 2019. [cited 2021 Mar 08]. Available from: https://doi.org/10.7916/d8-29kz-8d92.

Council of Science Editors:

Emerick AJ. Stellar Feedback and Chemical Evolution In Dwarf Galaxies. [Doctoral Dissertation]. Columbia University; 2019. Available from: https://doi.org/10.7916/d8-29kz-8d92

19. Titarenko, Anastasia. Indicateurs chimiques d’âge stellaire à l’ère de Gaia : Stellar chemical clocks in the Gaia era.

Degree: Docteur es, Sciences de la planète et de l'univers, 2018, Université Côte d'Azur (ComUE)

URL: http://www.theses.fr/2018AZUR4065

► Les étoiles enregistrent le passé dans leurs âges, leurs compositions chimiques et leur cinématique. Elles peuvent fournir des contraintes détaillées sur les premières époques de… (more)

▼ Les étoiles enregistrent le passé dans leurs âges, leurs compositions chimiques et leur cinématique. Elles peuvent fournir des contraintes détaillées sur les premières époques de la formation des galaxies, jusqu’aux redshifts supérieurs à deux (un recul d’environ 10 milliards d’années). En particulier, les âges stellaires sont essentiels pour la compréhension de l’histoire de la Voie Lactée et pour la comparaison avec les modèles d’évolution galactique.L’avènement de la mission spatiale Gaia ouvre la voie à l’estimation de l’âge pour de grands échantillons d’étoiles. En particulier, les méthodes basées sur l’ajustement d’isochrones peuvent être utilisées. En plus, les distances précises mesurées par Gaia permettent de développer les estimateurs d’âge indirects basés sur l’horloge d’évolution de la population stellaire. En fait, les schémas d’abondance chimique, imprimés sur les atmosphères stellaires, représentent les conditions du gaz au moment de la formation des étoiles à des redshifts supérieurs à deux. Les produits d’évolution chimique de différents canaux nucléosynthétiques peuvent donc fournir une approximation temporelle, qui, après l’étalonnage, peut être utilisé comme un estimateur d’âge.Cette thèse est centrée sur l’utilisation d’horloge chimique particulière : l’abondance [Y/Mg]. À cette fin, les premières données astrométriques de la mission Gaia ont été combinées avec des données spectroscopiques à haute résolution du catalogue AMBRE HARPS. Tout d’abord, l’identification des objets d’AMBRE a été améliorée grâce à la correspondance avec le catalogue 2MASS et la Gaia DR1. Au total, 6776 étoiles ont été identifiées.Deuxièmement, afin d’obtenir des estimations précises du rapport d’abondance [Y/Mg] pour les étoiles du disque galactique, l’outil automatisé GAUGUIN, intégré à la chaîne Gaia DPAC APSIS, a été optimisé et testé. En particulier, les capacités d’estimation d’abondances chimiques ont été améliorées pour des grilles de spectres synthétiques irrégulières, couvrant une large gamme de paramètres atmosphériques stellaires.Troisièmement, le ratio [Y/Mg] a été estimé pour environ 2000 étoiles à partir des données spectroscopiques d’AMBRE HARPS. Les erreurs internes et externes des abondances ont été soigneusement analysées. Les étoiles étudiées appartiennent principalement aux disques mince et épais galactique, dans la gamme de métallicité allant de –1,0 dex à 0,5 dex.Quatrièmement, grâce à l’estimation d’âge basée sur l’adaptation des isochrones pour 342 "turn-off" étoiles d’échantillon, la sensibilité à l’âge du rapport [Y/Mg] a été étudié. L’analyse révèle une corrélation claire entre [Y/Mg] et l’âge pour les étoiles du disque mince de différentes métallicités. Cela correspond aux études antérieures sur les étoiles de type solaire. De plus, aucune dépendance à la métallicité avec l’âge stellaire n’est détectée, donc le ratio [Y/Mg] peut être utilisé comme un indicateur fiable d’âge. Enfin, la relation [Y/Mg] versus l’âge présente une discontinuité entre les étoiles du disque épais autour de 9–10 Gyrs.… Advisors/Committee Members: Recio-Blanco, Alejandra (thesis director).

Subjects/Keywords: Étoiles : âges; Étoiles : abondances; Étoiles : évolution; Étoiles : paramètres fondamentaux; Galaxie : disque; Galaxie : évolution; Stars: ages; Stars: abundances; Stars: evolution; Stars: fundamental parameters; Galaxy: disk; Galaxy: evolution

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Titarenko, A. (2018). Indicateurs chimiques d’âge stellaire à l’ère de Gaia : Stellar chemical clocks in the Gaia era. (Doctoral Dissertation). Université Côte d'Azur (ComUE). Retrieved from http://www.theses.fr/2018AZUR4065

Chicago Manual of Style (16^th Edition):

Titarenko, Anastasia. “Indicateurs chimiques d’âge stellaire à l’ère de Gaia : Stellar chemical clocks in the Gaia era.” 2018. Doctoral Dissertation, Université Côte d'Azur (ComUE). Accessed March 08, 2021. http://www.theses.fr/2018AZUR4065.

MLA Handbook (7^th Edition):

Titarenko, Anastasia. “Indicateurs chimiques d’âge stellaire à l’ère de Gaia : Stellar chemical clocks in the Gaia era.” 2018. Web. 08 Mar 2021.

Vancouver:

Titarenko A. Indicateurs chimiques d’âge stellaire à l’ère de Gaia : Stellar chemical clocks in the Gaia era. [Internet] [Doctoral dissertation]. Université Côte d'Azur (ComUE); 2018. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2018AZUR4065.

Council of Science Editors:

Titarenko A. Indicateurs chimiques d’âge stellaire à l’ère de Gaia : Stellar chemical clocks in the Gaia era. [Doctoral Dissertation]. Université Côte d'Azur (ComUE); 2018. Available from: http://www.theses.fr/2018AZUR4065

University of Texas – Austin

20. Bergmann, Marcel Peter. Galaxy evolution: the relationship between structure, star formation, and environment.

Degree: PhD, Astronomy, 2002, University of Texas – Austin

URL: http://hdl.handle.net/2152/457

► I have conducted two separate observational tests of the current theoretical paradigm for galaxy formation and evolution, hierarchical galaxy formation in a Cold Dark Matter… (more)

▼ I have conducted two separate observational tests of the current theoretical paradigm for galaxy formation and evolution, hierarchical galaxy formation in a Cold Dark Matter dominated universe. The first project is a spectroscopic study of nineteen low surface brightness galaxies observed with the 9.2m Hobby-Eberly Telescope. I determine redshifts to all the galaxies, and report both emission line and absorption line index strengths, where appropriate. Correlations are found between the gas-phase metallicity indicators and the stellar indices which are sensitive to both metallicity and age. I interpret the star formation and chemical evolutionary histories of these galaxies using a combination of simple stellar population models and nebular emission models. The correlations observed between emission and absorption measurements place strong constraints on possible star formation histories. We find that low surface brightness galaxies are a diverse class, with properties as broad as those exhibited by the full range of high surface brightness galaxies. The second project is a study of the ages in early-type field galaxies, and a comparison with the ages found for a sample of cluster galaxies. I present preliminary results and interpretations based on new stellar population modelling methods. The new model explicitly accounts for age, metallicity, and α–abundance ratios for the stellar population, by making predictions for low resolution line indices. I measure the ages, metallicities, and α–abundance as a function of radius, from the center of each galaxy to beyond one effective radius. The gradients are consistent with younger, more metal rich stellar populations in the centers of most of the galaxies, but a constant α–abundance ratio within any one galaxy. I have generated an all-sky catalog which measures the local density of galaxies around every galaxy at cz<10,000 km s −1 . This facilitates the creation of low redshift field galaxy samples for follow-up study, in particular to study the effects of environment on galaxy evolution. I attempt to quantify the effects on the catalog of the varying spectroscopic survey completeness across the sky, and compare my local density measures with published field galaxy samples. The full catalog (42,024 galaxies, with ∼ 50 parameters per galaxy) is included in the electronic version of this dissertation. Advisors/Committee Members: Wheeler, J. Craig. (advisor), Hill, Gary J. (advisor).

Subjects/Keywords: Galaxies – Evolution; Stars – Formation; Stars – Structure

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bergmann, M. P. (2002). Galaxy evolution: the relationship between structure, star formation, and environment. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/457

Chicago Manual of Style (16^th Edition):

Bergmann, Marcel Peter. “Galaxy evolution: the relationship between structure, star formation, and environment.” 2002. Doctoral Dissertation, University of Texas – Austin. Accessed March 08, 2021. http://hdl.handle.net/2152/457.

MLA Handbook (7^th Edition):

Bergmann, Marcel Peter. “Galaxy evolution: the relationship between structure, star formation, and environment.” 2002. Web. 08 Mar 2021.

Vancouver:

Bergmann MP. Galaxy evolution: the relationship between structure, star formation, and environment. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2002. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2152/457.

Council of Science Editors:

Bergmann MP. Galaxy evolution: the relationship between structure, star formation, and environment. [Doctoral Dissertation]. University of Texas – Austin; 2002. Available from: http://hdl.handle.net/2152/457

21. André, Quentin. Ondes gravito-inertielles dans les étoiles et les planètes géantes : propagation, dissipation et échanges de moment cinétique : Gravito-inertial waves in stars and giant planets : propagation, dissipation and angular momentum transport.

Degree: Docteur es, Physique. Astronomie et astrophysique, 2019, Université de Paris (2019-....)

URL: http://www.theses.fr/2019UNIP7073

► Les ondes internes gravito-inertielles sont des ondes se propageant dans les milieux fluides stablement stratifiés en rotation. Leurs forces de rappel sont la poussée d'Archimède… (more)

▼ Les ondes internes gravito-inertielles sont des ondes se propageant dans les milieux fluides stablement stratifiés en rotation. Leurs forces de rappel sont la poussée d'Archimède et l'accélération de Coriolis. Elles sont capables de redistribuer de l'énergie et du moment cinétique du fait de leur dissipation et de leur possible déferlement non-linéaire, jouant ainsi un rôle crucial dans l’évolution dynamique des corps dans lesquels elles se propagent. Dans cette thèse, nous nous attachons à caractériser leur propagation, leur amortissement et les échanges de moment cinétique qu’elles induisent, dans les environnements complexes que sont les intérieurs stellaires et de planètes géantes.Au sein des planètes géantes, nous étudions la propagation et la dissipation d’ondes gravito-inertielles de marée, dans une région de convection stratifiée susceptible de se développer proche du cœur. Nous nous intéressons tout d’abord à leur propagation libre et nous montrons qu’une onde incidente sur une telle région est efficacement transmise à condition qu’elle soit résonante avec un de ses modes propres. Sinon, l’onde est réfléchie et ne pénètre pas dans les régions plus profondes de la planète. Ensuite, nous étudions numériquement la dissipation de marée induite lorsque ces ondes sont excitées par un forçage gravitationnel dû à la présence d’un satellite. Nous montrons que le taux de dissipation de marée est en moyenne augmenté par rapport à un milieu purement convectif. Les contributions les plus importantes à cette augmentation proviennent de la dissipation des ondes gravito-inertielles résonantes avec les modes propres de la région de convection stratifiée, qui sont aussi celles qui sont efficacement transmises. Ces résultats sont compatibles avec les hauts taux de dissipation de marée récemment observés dans Jupiter et Saturne.Dans les zones radiatives des étoiles, nous présentons en premier lieu une étude semi-analytique linéaire de l’influence de la rotation globale et différentielle, sur le transport de moment cinétique induit par la dissipation des ondes gravito-inertielles. Dans un modèle équatorial, nous montrons que la rotation a pour effet l’augmentation de la dissipation thermique des ondes. Celle-ci est particulièrement significative dans leur région d’excitation, modifiant ainsi le dépôt de moment cinétique. Nous montrons que cet effet se révèle d’autant plus efficace que l’étoile est jeune et massive. En parallèle de ce travail semi-analytique, cette thèse s’est attachée à développer un modèle 3D non-linéaire ab initio d’une étoile massive couplant le coeur convectif à une enveloppe radiative étendue, sous l’influence de la rotation. L’analyse détaillée de simulations numériques à haute performance, réalisées avec le code ASH, nous a permis de caractériser les propriétés du spectre d’excitation des ondes et des modes résonants qui s’établissent dans l’enveloppe radiative. Proche de la surface de l’étoile, nous montrons que les ondes peuvent atteindre une amplitude suffisante pour interagir de manière significative… Advisors/Committee Members: Mathis, Stéphane (thesis director), Brun, Allan Sacha (thesis director).

Subjects/Keywords: Interactions de marées; Hydrodynamics; Modelisation; Numerical simulation; Waves; Convection; Giant planets; Tides; Stars – Rotation; Stars – Evolution; Massive stars

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

André, Q. (2019). Ondes gravito-inertielles dans les étoiles et les planètes géantes : propagation, dissipation et échanges de moment cinétique : Gravito-inertial waves in stars and giant planets : propagation, dissipation and angular momentum transport. (Doctoral Dissertation). Université de Paris (2019-....). Retrieved from http://www.theses.fr/2019UNIP7073

Chicago Manual of Style (16^th Edition):

André, Quentin. “Ondes gravito-inertielles dans les étoiles et les planètes géantes : propagation, dissipation et échanges de moment cinétique : Gravito-inertial waves in stars and giant planets : propagation, dissipation and angular momentum transport.” 2019. Doctoral Dissertation, Université de Paris (2019-....). Accessed March 08, 2021. http://www.theses.fr/2019UNIP7073.

MLA Handbook (7^th Edition):

André, Quentin. “Ondes gravito-inertielles dans les étoiles et les planètes géantes : propagation, dissipation et échanges de moment cinétique : Gravito-inertial waves in stars and giant planets : propagation, dissipation and angular momentum transport.” 2019. Web. 08 Mar 2021.

Vancouver:

André Q. Ondes gravito-inertielles dans les étoiles et les planètes géantes : propagation, dissipation et échanges de moment cinétique : Gravito-inertial waves in stars and giant planets : propagation, dissipation and angular momentum transport. [Internet] [Doctoral dissertation]. Université de Paris (2019-....); 2019. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2019UNIP7073.

Council of Science Editors:

André Q. Ondes gravito-inertielles dans les étoiles et les planètes géantes : propagation, dissipation et échanges de moment cinétique : Gravito-inertial waves in stars and giant planets : propagation, dissipation and angular momentum transport. [Doctoral Dissertation]. Université de Paris (2019-....); 2019. Available from: http://www.theses.fr/2019UNIP7073

University of Arizona

22. COOK, KEM HOLLAND. ASYMPTOTIC GIANT BRANCH POPULATIONS IN COMPOSITE STELLAR SYSTEMS.

Degree: 1987, University of Arizona

URL: http://hdl.handle.net/10150/184208

► This dissertation presents a technique for the identification and classification of late-type stars and for the estimation of M star metallicities. The technique uses broad-band,… (more)

Subjects/Keywords: Stars – Classification.; Stars – Evolution.; Cool stars – Classification.; Astronomy – Observations.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

COOK, K. H. (1987). ASYMPTOTIC GIANT BRANCH POPULATIONS IN COMPOSITE STELLAR SYSTEMS. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/184208

Chicago Manual of Style (16^th Edition):

COOK, KEM HOLLAND. “ASYMPTOTIC GIANT BRANCH POPULATIONS IN COMPOSITE STELLAR SYSTEMS. ” 1987. Doctoral Dissertation, University of Arizona. Accessed March 08, 2021. http://hdl.handle.net/10150/184208.

MLA Handbook (7^th Edition):

COOK, KEM HOLLAND. “ASYMPTOTIC GIANT BRANCH POPULATIONS IN COMPOSITE STELLAR SYSTEMS. ” 1987. Web. 08 Mar 2021.

Vancouver:

COOK KH. ASYMPTOTIC GIANT BRANCH POPULATIONS IN COMPOSITE STELLAR SYSTEMS. [Internet] [Doctoral dissertation]. University of Arizona; 1987. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10150/184208.

Council of Science Editors:

COOK KH. ASYMPTOTIC GIANT BRANCH POPULATIONS IN COMPOSITE STELLAR SYSTEMS. [Doctoral Dissertation]. University of Arizona; 1987. Available from: http://hdl.handle.net/10150/184208

York University

23. Moore, Keavin Matthew. Tatooine's Future: Dynamical Evolution of Planets Orbiting Two Stars.

Degree: MSc -MS, Physics And Astronomy, 2018, York University

URL: http://hdl.handle.net/10315/34393

► Science fiction has long teased our imaginations with tales of planets with two suns. How these planets form and evolve, and their survival prospects, are… (more)

Subjects/Keywords: Astronomy; Astronomy; Astrophysics; Planets; Exoplanets; Extra-solar planets; Circumbinary planets; Stars; Binary stars; Close binary stars; Stellar evolution; Common envelope; Survival; Dynamical evolution; Orbital evolution; Tatooine; Suns

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Moore, K. M. (2018). Tatooine's Future: Dynamical Evolution of Planets Orbiting Two Stars. (Masters Thesis). York University. Retrieved from http://hdl.handle.net/10315/34393

Chicago Manual of Style (16^th Edition):

Moore, Keavin Matthew. “Tatooine's Future: Dynamical Evolution of Planets Orbiting Two Stars.” 2018. Masters Thesis, York University. Accessed March 08, 2021. http://hdl.handle.net/10315/34393.

MLA Handbook (7^th Edition):

Moore, Keavin Matthew. “Tatooine's Future: Dynamical Evolution of Planets Orbiting Two Stars.” 2018. Web. 08 Mar 2021.

Vancouver:

Moore KM. Tatooine's Future: Dynamical Evolution of Planets Orbiting Two Stars. [Internet] [Masters thesis]. York University; 2018. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10315/34393.

Council of Science Editors:

Moore KM. Tatooine's Future: Dynamical Evolution of Planets Orbiting Two Stars. [Masters Thesis]. York University; 2018. Available from: http://hdl.handle.net/10315/34393

University of Arizona

24. Boroson, Todd Allan. CHEMICAL ABUNDANCES AND PHOTOMETRIC PARAMETERS IN THE BULGES OF SPIRAL GALAXIES .

Degree: 1980, University of Arizona

URL: http://hdl.handle.net/10150/282503

► The relation between central or mean metallicity and luminosity in elliptical galaxies is a well observed phenomenon. Theoretical explanations proposed for this relation include scenarios… (more)

▼ The relation between central or mean metallicity and luminosity in elliptical galaxies is a well observed phenomenon. Theoretical explanations proposed for this relation include scenarios in which peak metallicities are determined either by the epoch at which the remaining gas is expelled from the galaxy by supernova-driven winds, or by the efficiency of star formation following a series of mergers by small stellar/gaseous subsystems. These explanations suggest that an investigation of the metallicity-luminosity relation for spiral galaxies might have implications for galaxy formation models and for the origin of SO galaxies. The existing evidence concerning SO's points to a relation between mean metallicity and total luminosity. The problem of measuring metal abundances in the nuclei of spiral galaxies is that the line strength variations due to metallicity changes must be distinguished from those due to a filling in of the lines by the continuum from a young population. This was accomplished by measuring absorption line indices for Mg b and for a CN band at λ3880. Nuclear spectra of twenty ellipticals, obtained with a reticon detector, show these two indices to be well correlated for pure old populations; models including the effects of young stars show a very different trajectory for age effects. A procedure is thus defined for determining the metallicity of the population and the fraction of light coming from the young component, and this procedure is applied to observations of 25 spiral galaxies. A comparison of the results of this analysis with detailed population syntheses for six galaxies confirms the correctness of the procedure. In order to obtain bulge luminosities and bulge-to-disk ratios, photographic plates of twenty-two of the spirals were obtained. This material was digitized and reduced to a series of radial luminosity profiles for each galaxy. A procedure was established for decomposing the profiles into disk and bulge contributions. In addition to the desired gross parameters of the bulge and disk, the inclinations and true bulge flattenings for some of the galaxies are accurately determined. A discussion of the results of this analysis deals with the nature of departures from the exponential fitting function for some disks, a decomposition of the Hubble sequence into quantitative parameters, and the implication of the distribution of true bulge flattenings. The metallicities and luminosities are then combined, and two tests indicate that in spiral galaxies, central metallicity and bulge luminosity follow the same relation seen in ellipticals. The implications of this result are twofold. First, galaxy formation models in which the disk material can affect the processes which determine the central metallicity in the bulge are ruled out. Specifically, it is likely that the disks of spiral galaxies are not undergoing vigorous star formation at the time the bulge ceases forming stars. A picture in which the disk material has not yet accreted on to the galaxy at this time is also quite consistent. A… Advisors/Committee Members: Weymann, Ray J (advisor).

Subjects/Keywords: Galaxies – Spectra.; Galaxies – Evolution.; Stars – Evolution.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Boroson, T. A. (1980). CHEMICAL ABUNDANCES AND PHOTOMETRIC PARAMETERS IN THE BULGES OF SPIRAL GALAXIES . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/282503

Chicago Manual of Style (16^th Edition):

Boroson, Todd Allan. “CHEMICAL ABUNDANCES AND PHOTOMETRIC PARAMETERS IN THE BULGES OF SPIRAL GALAXIES .” 1980. Doctoral Dissertation, University of Arizona. Accessed March 08, 2021. http://hdl.handle.net/10150/282503.

MLA Handbook (7^th Edition):

Boroson, Todd Allan. “CHEMICAL ABUNDANCES AND PHOTOMETRIC PARAMETERS IN THE BULGES OF SPIRAL GALAXIES .” 1980. Web. 08 Mar 2021.

Vancouver:

Boroson TA. CHEMICAL ABUNDANCES AND PHOTOMETRIC PARAMETERS IN THE BULGES OF SPIRAL GALAXIES . [Internet] [Doctoral dissertation]. University of Arizona; 1980. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10150/282503.

Council of Science Editors:

Boroson TA. CHEMICAL ABUNDANCES AND PHOTOMETRIC PARAMETERS IN THE BULGES OF SPIRAL GALAXIES . [Doctoral Dissertation]. University of Arizona; 1980. Available from: http://hdl.handle.net/10150/282503

25. Amard, Louis. Évolution de la rotation des étoiles jeunes de faible masse : Rotational evolution of young low-mass stars.

Degree: Docteur es, Physique, 2016, Montpellier; Observatoire de Genève (Suisse)

URL: http://www.theses.fr/2016MONTT258

►

Le moment cinétique d’une étoile, comme sa masse ou sa composition chimique, est l’une de ses propriétés fondamentales, l’un de celles qui varient à cours… (more)

▼

Le moment cinétique d’une étoile, comme sa masse ou sa composition chimique, est l’une de ses propriétés fondamentales, l’un de celles qui varient à cours du temps et influent sur la structure de l’étoile. Celui-ci peut être global, on l’observe alors à travers la vitesse de rotation de surface d’une étoile, ou local, auquel cas il nous faut sonder l’intérieur stellaire et étudier les processus de redistribution au sein des régions internes du moment cinétique. Au cours de cette thèse dans le cadre du projet ToUpiES, nous nous sommes intéressés en particulier à l’évolution du moment cinétique des étoiles de faible masse au cours de leur jeunesse, qui est une période critique de leur vie en ce qui concerne l’impact et l’évolution du moment cinétique. Nous avons d’abord inclus au sein du code d’évolution STAREVOL les prescriptions les plus à jour pour l’extraction du moment cinétique par les vents magnétisés. L’étude systématique des combinaisons de ce freinage avec différentes prescriptions existantes pour le traitement de la turbulence horizontale et verticale dans la zone radiative des étoiles, nous a permis de sélectionner un jeu de prescriptions capable de reproduire, les périodes de rotation dans les amas ouverts pour une étoile de type solaire. Nous comparons ensuite l’application de ces processus de transport et d’extraction du moment cinétique à un modèle de 1, 2 masse solaire, aux autres processus jugés potentiellement efficaces pour transport le moment cinétique à ce jour (ondes internes de gravités, instabilité MHD de Tayler-Spruit, modes de gravités). Cela nous a permis de présenter dans chacun des cas les spécificités du profil de rotation prédit par ces différents modes de transport. Puis, nous avons mis en place un modèle rotationnel fonctionnel adapté à l’ensemble des étoiles de faible masse, permettant entre autre de reproduire les périodes de rotation observées dans les amas jeunes pour les étoiles de faible masse (avec une masse comprise entre 0, 2 et 1, 1 M⊙). Ceci a donné lieu à une grille de modèle d’évolution unique à ce jour. Enfin, cette grille a été utilisée dans le cadre de travaux dans différents domaines, tels que l’impact de l’évolution stellaire sur l’habitabilité d’un système, la caractérisation d’étoiles-hôte ou encore l’étude de l’évolution de la topologie magnétique au cours des phases jeunes.

The angular momentum content of a star, as its mass or its chemical composition is one of the fundamental properties of a star, one of those that evolves with time and modify the stellar structure. The angular momentum can be studied as a global property, we can then observe it through the surface rotation velocity, or a local property that vary inside the star, we therefore have to probe the stellar radiation zone and study the secular angular momentum redistribution processes that happen in this region. During this PhD, in the frame of the ToUpiES project, we have been especially interested in the evolution of the…

Advisors/Committee Members: Palacios, Ana (thesis director), Charbonnel, Corinne (thesis director).

Subjects/Keywords: Evolution stellaire; Rotation; Magnétohydrodynamique; Etoiles jeunes; Stellar Evolution; Rotation; Young stars; Magnetohydrodynamics

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Amard, L. (2016). Évolution de la rotation des étoiles jeunes de faible masse : Rotational evolution of young low-mass stars. (Doctoral Dissertation). Montpellier; Observatoire de Genève (Suisse). Retrieved from http://www.theses.fr/2016MONTT258

Chicago Manual of Style (16^th Edition):

Amard, Louis. “Évolution de la rotation des étoiles jeunes de faible masse : Rotational evolution of young low-mass stars.” 2016. Doctoral Dissertation, Montpellier; Observatoire de Genève (Suisse). Accessed March 08, 2021. http://www.theses.fr/2016MONTT258.

MLA Handbook (7^th Edition):

Amard, Louis. “Évolution de la rotation des étoiles jeunes de faible masse : Rotational evolution of young low-mass stars.” 2016. Web. 08 Mar 2021.

Vancouver:

Amard L. Évolution de la rotation des étoiles jeunes de faible masse : Rotational evolution of young low-mass stars. [Internet] [Doctoral dissertation]. Montpellier; Observatoire de Genève (Suisse); 2016. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2016MONTT258.

Council of Science Editors:

Amard L. Évolution de la rotation des étoiles jeunes de faible masse : Rotational evolution of young low-mass stars. [Doctoral Dissertation]. Montpellier; Observatoire de Genève (Suisse); 2016. Available from: http://www.theses.fr/2016MONTT258

Macquarie University

26. Douchin, Dimitri. Estimating the binary fraction of central stars of planetary nebulae.

Degree: 2015, Macquarie University

URL: http://hdl.handle.net/1959.14/1068333

►

"A PhD thesis submitted to Macquarie University in cotutelle with Université de Montpellier 2 Department of Physics and Astronomy January 2015"

Abstract and summary also… (more)

▼

"A PhD thesis submitted to Macquarie University in cotutelle with Université de Montpellier 2 Department of Physics and Astronomy January 2015"

Abstract and summary also in French.

1. Introduction – 2. The NIR excess technique – 3. The NIR excess technique: observations and analysis – 4. NIR excess search from available surveys – 5. The photometric variability technique – 6. The radial velocity variability technique – 7. The binary fraction of CSPN – 8. Conclusion – Appendices.

Planetary nebulae are the end-products of intermediate-mass stars evolution, following a phase of spherical expansion of their atmospheres at the end of their lives. Observationally, it has been estimated that 80% of them have non-spherical shapes. Such a high fraction is puzzling and has occupied the planetary nebula community for more than 30 years. One scenario that would allow to justify the observed shapes is that a comparable fraction of the progenitors of central stars of planetary nebula (CSPN) are not single, but possess a companion. The shape of the nebulae would then be the result of an interaction with this companion. The high fraction of non-spherical planetary nebulae would thus imply a high fraction of binary central stars of planetary nebula, making binarity a preferred channel for planetary nebula formation. After presenting the current state of knowledge regarding planetary nebula formation and shaping and reviewing the diverse efforts to find binaries in planetary nebulae, I present my work to detect a near-infrared excess that would be the signature of the presence of cool companions. The first part of the project consists in the analysis of data and photometry acquired and conducted by myself. The second part details an attempt to make use of archived datasets: the Sloan Digital Sky Survey Data Release 7 optical survey and the extended database assembled by Frew (2008). I also present results from a radial velocity analysis of VLT/UVES spectra for 14 objects aiming to the detection of spectroscopic companions. Finally I give details of the analysis of optical photometry data from our observations associated to the detection of companions around centrals star of planetary nebula using the photometric variability technique. The main result of this thesis is from the near-infrared excess studies which I combine with previouslypublished data. I conclude that if the detected red and NIR flux excess is indicative of a stellar companion then the binary fraction is larger than what we may expect based on the main-sequence progenitor population binary fraction and therefore conclude that binarity is a preferential channel for the formation of planetary nebula. I finish by underlining the need for a sample size of ~150 objects to decrease the uncertainty on the planetary nebula population binary fraction and increase the statistical significance of this result.

1 online resource (xxii, 176 pages) illustrations

Advisors/Committee Members: Macquarie University. Department of Physics and Astronomy, Université des sciences et techniques du Languedoc.

Subjects/Keywords: Planetary nebulae; Double stars – Evolution; stellar physics; astronomy; astrophysics; planetary nebula; binary star; stellar evolution

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Douchin, D. (2015). Estimating the binary fraction of central stars of planetary nebulae. (Doctoral Dissertation). Macquarie University. Retrieved from http://hdl.handle.net/1959.14/1068333

Chicago Manual of Style (16^th Edition):

Douchin, Dimitri. “Estimating the binary fraction of central stars of planetary nebulae.” 2015. Doctoral Dissertation, Macquarie University. Accessed March 08, 2021. http://hdl.handle.net/1959.14/1068333.

MLA Handbook (7^th Edition):

Douchin, Dimitri. “Estimating the binary fraction of central stars of planetary nebulae.” 2015. Web. 08 Mar 2021.

Vancouver:

Douchin D. Estimating the binary fraction of central stars of planetary nebulae. [Internet] [Doctoral dissertation]. Macquarie University; 2015. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/1959.14/1068333.

Council of Science Editors:

Douchin D. Estimating the binary fraction of central stars of planetary nebulae. [Doctoral Dissertation]. Macquarie University; 2015. Available from: http://hdl.handle.net/1959.14/1068333

Rochester Institute of Technology

27. Freeman, Marcus J. Multiwavelength Imaging of Planetary Nebulae: Resolving & Disentangling Structure.

Degree: PhD, School of Physics and Astronomy (COS), 2015, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/8888

► Planetary nebulae (PNe) represent the late stages of low-mass stellar evolution. The formation of the myriad of PNe morphologies involves processes that are present… (more)

▼ Planetary nebulae (PNe) represent the late stages of low-mass stellar evolution. The formation of the myriad of PNe morphologies involves processes that are present in many other astrophysical systems such as the wind-blown bubbles of massive stars. In this dissertation we present the result of an X-ray study of PNe, and two modeling projects that incorporate the resulting data with the goal of furthering our understanding of their X-ray properties and morphologies, and the 3D multiwavelength structure of PNe. This work expands the Chandra Planetary Nebula Survey (ChanPlaNS), which was designed to investigate X-ray emission from PNe, frm 35 to 59 objects. The results from Cycle 14 Chandra observations of 24 PNe brought the overall ChanPlaNS diffuse X-ray detection rate to ~27% and the point source detection rate to ~36%. The detection of diffuse X-ray emission is unmistakably associated with young (<~5 x 10³ yr), compact (Rneb <~0.15 pc) PNe that exhibit closed elliptical structures and high electron densities (ne >~ 10³ cm⁻³). Utilizing the ChanPlaNS data for 14 PNe that exhibit diffuse X-ray emission, we constructed simple, spherically symmetric two-phase models using the astrophysical modeling tool, SHAPE. Our models consisted of a hot bubble and swept-up shell with the intent of investigating th X-ray morphology of these objects and the extinction caused by the swept-up shell. We compared simulated and observed radial profiles and we conclude that while most (~79%) PNe are best described by a limb-darkened X-ray morphology, this is due to nebular extinction of an intrinsically limb-brightened hot bubble structure. Expanding upon our two-phase model, we used SHAPE to generate a 3D model of the brightest diffuse X-ray PN, BD+30°3639, with the model constrained by previously published multiwavelength data extending from the radio to the X-ray regimes. Our aim was to investigate the multiwavelength 3D morphology of this well-studied nebula and draw connections with other PNe. We interpreted kinematic and observational data to best fit our model with observations and found that the inherent structure shares similarities with several other PNe, suggesting a common evolutionary path. Advisors/Committee Members: Joel H. Kastner.

Subjects/Keywords: Modeling; Planetary nebulae; Stars; Stellar evolution; X-rays

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Freeman, M. J. (2015). Multiwavelength Imaging of Planetary Nebulae: Resolving & Disentangling Structure. (Doctoral Dissertation). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/8888

Chicago Manual of Style (16^th Edition):

Freeman, Marcus J. “Multiwavelength Imaging of Planetary Nebulae: Resolving & Disentangling Structure.” 2015. Doctoral Dissertation, Rochester Institute of Technology. Accessed March 08, 2021. https://scholarworks.rit.edu/theses/8888.

MLA Handbook (7^th Edition):

Freeman, Marcus J. “Multiwavelength Imaging of Planetary Nebulae: Resolving & Disentangling Structure.” 2015. Web. 08 Mar 2021.

Vancouver:

Freeman MJ. Multiwavelength Imaging of Planetary Nebulae: Resolving & Disentangling Structure. [Internet] [Doctoral dissertation]. Rochester Institute of Technology; 2015. [cited 2021 Mar 08]. Available from: https://scholarworks.rit.edu/theses/8888.

Council of Science Editors:

Freeman MJ. Multiwavelength Imaging of Planetary Nebulae: Resolving & Disentangling Structure. [Doctoral Dissertation]. Rochester Institute of Technology; 2015. Available from: https://scholarworks.rit.edu/theses/8888

Vilnius University

28. Stonkutė, Edita. Chemical composition of kinematically identified galactic stellar group.

Degree: PhD, Physics, 2013, Vilnius University

URL: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093107-33619 ;

►

A number of stellar streams, moving and kinematic groups were identified in the Milky Way galaxy. Some of them are suspected to originate from accreted… (more)

▼

A number of stellar streams, moving and kinematic groups were identified in the Milky Way galaxy. Some of them are suspected to originate from accreted satellites. Can we also find such traces of ancient merger events in the solar neighbourhood? Helmi et al. (2006) identified three new coherent groups of stars in the Geneva-Copenhagen survey (Nordström et al. 2004) and suggested that those might correspond to remains of disrupted satellites. With the detailed chemical composition analysis of the newly identified kinematic group we aim to contribute to the Galactic substructure studies. The main aim of the study is to perform a high-resolution spectroscopic elemental abundance analysis in stars belonging to one of the newly identified kinematic groups and to compare the results with other stars in the Galactic disc. We performed the detailed chemical analysis of 21 stars attributed to Group 3 of the Geneva-Copenhagen survey and six comparison Galactic thin disc stars. The main atmospheric parameters and abundances of 22 chemical elements were determined. All programme stars are overabundant in oxygen and α-elements compared with the Galactic thin-disc. This abundance pattern has similar characteristics to those of the Galactic thick disc. The abundances of chemical elements produced predominantly by the r-process are overabundant in comparison with Galactic thin-disc dwarfs of the same metallicity. The abundances of iron-group elements and chemical elements produced mainly by... [to full text]

Paukščių Tako galaktikoje yra identifikuota žvaigždžių srautų, judančių bei kinematinių grupių, kurių kilmė siejama su įkritusiomis galaktikomis. Aktualu ištirti, ar yra tokių senųjų substruktūrų pėdsakų mūsų Saulės aplinkoje? Helmi ir kt. (2006), panaudoję Nordström ir kt. (2004) Ženevos–Kopenhagos apžvalgos (ŽKA) katalogą, identifikavo tris naujas koherentines žvaigždžių grupes, kurios pasižymi išskirtiniais kinematiniais parametrais ir gali būti užgalaktinės kilmės. Šiuo disertacijos darbu siekiama prisidėti prie Galaktikos substruktūrų tyrimų, nustatant detalią cheminę vienos iš Helmi ir kt. identifikuotų žvaigždžių grupių sudėtį. Svarbu išsiaiškinant, ar ŽKA kinematinės grupės žvaigždžių atmosferų cheminė sudėtis skiriasi nuo Galaktikos disko žvaigždžių. Nustatėme 21 3–osios ŽKA kinematinės grupės bei 6 palyginamųjų plonojo disko žvaigždžių atmosferų pagrindinius parametrus bei 22 cheminių elementų gausas. Kinematinės žvaigždžių grupės deguonies ir α–elementų gausos yra padidėjusios lyginant su plonuoju disku ir yra panašios į storojo disko. Cheminių elementų, daugiausia pagaminamų s–procese, gausos ir geležies grupės elementų gausos yra panašios į to paties metalingumo plonojo disko nykštukių cheminių elementų gausas, o cheminių elementų, daugiausia pagaminamų r–procese, gausos yra padidėjusios lyginant su plonuoju disku. Panaši cheminė tirtos kinematinės grupės bei storojo Galaktikos disko sudėtis rodo, kad kinematinės žvaigždžių grupės ir storojo disko žvaigždžių... [toliau žr. visą tekstą]

Advisors/Committee Members: Tautvaišienė, Gažina (Doctoral dissertation supervisor), Zdanavičius, Kazimieras (Doctoral dissertation committee chair), Miškinis, Paulius (Doctoral dissertation committee member), Kazlauskas, Algirdas Stasius (Doctoral dissertation committee member), Lazauskaitė, Romualda (Doctoral dissertation committee member), Mickevičius, Saulius (Doctoral dissertation committee member), Bartašiūtė, Stanislava (Doctoral dissertation opponent), Korn, Andreas (Doctoral dissertation opponent).

Subjects/Keywords: Galaxy evolution; Formation; Stars; Abundance; Galaktikos evoliucija; Formavimasis; Žvaigždės; Gausos

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Stonkutė, E. (2013). Chemical composition of kinematically identified galactic stellar group. (Doctoral Dissertation). Vilnius University. Retrieved from http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093107-33619 ;

Chicago Manual of Style (16^th Edition):

Stonkutė, Edita. “Chemical composition of kinematically identified galactic stellar group.” 2013. Doctoral Dissertation, Vilnius University. Accessed March 08, 2021. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093107-33619 ;.

MLA Handbook (7^th Edition):

Stonkutė, Edita. “Chemical composition of kinematically identified galactic stellar group.” 2013. Web. 08 Mar 2021.

Vancouver:

Stonkutė E. Chemical composition of kinematically identified galactic stellar group. [Internet] [Doctoral dissertation]. Vilnius University; 2013. [cited 2021 Mar 08]. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093107-33619 ;.

Council of Science Editors:

Stonkutė E. Chemical composition of kinematically identified galactic stellar group. [Doctoral Dissertation]. Vilnius University; 2013. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093107-33619 ;

Vilnius University

29. Stonkutė, Edita. Cheminė kinematiškai identifikuotos Galaktikos žvaigždžių grupės sudėtis.

Degree: Dissertation, Physics, 2013, Vilnius University

URL: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093256-69980 ;

►

Paukščių Tako galaktikoje yra identifikuota žvaigždžių srautų, judančių bei kinematinių grupių, kurių kilmė siejama su įkritusiomis galaktikomis. Aktualu ištirti, ar yra tokių senųjų substruktūrų pėdsakų… (more)

▼

Paukščių Tako galaktikoje yra identifikuota žvaigždžių srautų, judančių bei kinematinių grupių, kurių kilmė siejama su įkritusiomis galaktikomis. Aktualu ištirti, ar yra tokių senųjų substruktūrų pėdsakų mūsų Saulės aplinkoje? Helmi ir kt. (2006), panaudoję Nordström ir kt. (2004) Ženevos–Kopenhagos apžvalgos (ŽKA) katalogą, identifikavo tris naujas koherentines žvaigždžių grupes, kurios pasižymi išskirtiniais kinematiniais parametrais ir gali būti užgalaktinės kilmės. Šiuo disertacijos darbu siekiama prisidėti prie Galaktikos substruktūrų tyrimų, nustatant detalią cheminę vienos iš Helmi ir kt. identifikuotų žvaigždžių grupių sudėtį. Svarbu išsiaiškinant, ar ŽKA kinematinės grupės žvaigždžių atmosferų cheminė sudėtis skiriasi nuo Galaktikos disko žvaigždžių. Nustatėme 21 3–osios ŽKA kinematinės grupės bei 6 palyginamųjų plonojo disko žvaigždžių atmosferų pagrindinius parametrus bei 22 cheminių elementų gausas. Kinematinės žvaigždžių grupės deguonies ir α–elementų gausos yra padidėjusios lyginant su plonuoju disku ir yra panašios į storojo disko. Cheminių elementų, daugiausia pagaminamų s–procese, gausos ir geležies grupės elementų gausos yra panašios į to paties metalingumo plonojo disko nykštukių cheminių elementų gausas, o cheminių elementų, daugiausia pagaminamų r–procese, gausos yra padidėjusios lyginant su plonuoju disku. Panaši cheminė tirtos kinematinės grupės bei storojo Galaktikos disko sudėtis rodo, kad kinematinės žvaigždžių grupės ir storojo disko žvaigždžių... [toliau žr. visą tekstą]

A number of stellar streams, moving and kinematic groups were identified in the Milky Way galaxy. Some of them are suspected to originate from accreted satellites. Can we also find such traces of ancient merger events in the solar neighbourhood? Helmi et al. (2006) identified three new coherent groups of stars in the Geneva-Copenhagen survey (Nordström et al. 2004) and suggested that those might correspond to remains of disrupted satellites. With the detailed chemical composition analysis of the newly identified kinematic group we aim to contribute to the Galactic substructure studies. The main aim of the study is to perform a high-resolution spectroscopic elemental abundance analysis in stars belonging to one of the newly identified kinematic groups and to compare the results with other stars in the Galactic disc. We performed the detailed chemical analysis of 21 stars attributed to Group 3 of the Geneva-Copenhagen survey and six comparison Galactic thin disc stars. The main atmospheric parameters and abundances of 22 chemical elements were determined. All programme stars are overabundant in oxygen and α-elements compared with the Galactic thin-disc. This abundance pattern has similar characteristics to those of the Galactic thick disc. The abundances of chemical elements produced predominantly by the r-process are overabundant in comparison with Galactic thin-disc dwarfs of the same metallicity. The abundances of iron-group elements and chemical elements produced mainly by... [to full text]

Advisors/Committee Members: Tautvaišienė, Gažina (Doctoral dissertation supervisor), Zdanavičius, Kazimieras (Doctoral dissertation committee chair), Miškinis, Paulius (Doctoral dissertation committee member), Kazlauskas, Algirdas Stasius (Doctoral dissertation committee member), Lazauskaitė, Romualda (Doctoral dissertation committee member), Mickevičius, Saulius (Doctoral dissertation committee member), Bartašiūtė, Stanislava (Doctoral dissertation opponent), Korn, Andreas (Doctoral dissertation opponent).

Subjects/Keywords: Galatikos evoliucija; Formavimasis; Žvaigždės; Gausos; Galaxy evolution; Formation; Stars; Abundance

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Stonkutė, E. (2013). Cheminė kinematiškai identifikuotos Galaktikos žvaigždžių grupės sudėtis. (Doctoral Dissertation). Vilnius University. Retrieved from http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093256-69980 ;

Chicago Manual of Style (16^th Edition):

Stonkutė, Edita. “Cheminė kinematiškai identifikuotos Galaktikos žvaigždžių grupės sudėtis.” 2013. Doctoral Dissertation, Vilnius University. Accessed March 08, 2021. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093256-69980 ;.

MLA Handbook (7^th Edition):

Stonkutė, Edita. “Cheminė kinematiškai identifikuotos Galaktikos žvaigždžių grupės sudėtis.” 2013. Web. 08 Mar 2021.

Vancouver:

Stonkutė E. Cheminė kinematiškai identifikuotos Galaktikos žvaigždžių grupės sudėtis. [Internet] [Doctoral dissertation]. Vilnius University; 2013. [cited 2021 Mar 08]. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093256-69980 ;.

Council of Science Editors:

Stonkutė E. Cheminė kinematiškai identifikuotos Galaktikos žvaigždžių grupės sudėtis. [Doctoral Dissertation]. Vilnius University; 2013. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130925_093256-69980 ;

30. Potter, Adrian Thomas. Rotation and magnetism in massive stars.

Degree: PhD, 2012, University of Cambridge

URL: http://www.dspace.cam.ac.uk/handle/1810/243617https://www.repository.cam.ac.uk/bitstream/1810/243617/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/243617/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/243617/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/243617/9/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/7/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/10/potterThesis.pdf.jpg

► Rotation has a number of important effects on the evolution of stars. Apart from structural changes because of the centrifugal force, turbulent mixing and meridional… (more)

▼ Rotation has a number of important effects on the evolution of stars. Apart from structural changes because of the centrifugal force, turbulent mixing and meridional circulation can dramatically affect a star's chemical evolution. This leads to changes in the surface temperature and luminosity as well as modifying its lifetime. Rotation decreases the surface gravity, causes enhanced mass loss and leads to surface abundance anomalies of various chemical isotopes all of which have been observed. The replication of these physical effects with simple stellar evolution models is very difficult and has resulted in the use of numerous different formulations to describe the physics. We have adapted the Cambridge stellar evolution code to incorporate a number of different physical models for rotation, including several treatments of angular momentum transport in convection zones. We compare detailed grids of stellar evolution models along with simulated stellar populations to identify the key differences between them. We then consider how these models relate to observed data. Models of rotationally-driven dynamos in stellar radiative zones have suggested that magnetohydrodynamic transport of angular momentum and chemical composition can dominate over the otherwise purely hydrodynamic processes. If this is the case then a proper consideration of the interaction between rotation and magnetic fields is essential. We have adapted our purely hydrodynamic model to include the evolution of the magnetic field with a pair of time-dependent advection – diffusion equations coupled with the equations for the evolution of the angular momentum distribution and stellar structure. This produces a much more complete, though still reasonably simple, model for the magnetic field evolution. We consider how the surface field strength varies during the main-sequence evolution and compare the surface enrichment of nitrogen for a simulated stellar population with observations. Strong magnetic fields are also observed at the end of the stellar lifetime. The surface magnetic field strength of white dwarfs is observed to vary from very little up to 10^9G. As well as considering the main-sequence evolution of magnetic fields we also look at how the strongest magnetic fields in white dwarfs may be generated by dynamo action during the common envelope phase of strongly interacting binary stars. The resulting magnetic field depends strongly on the electrical conductivity of the white dwarf, the lifetime of the convective envelope and the variability of the magnetic dynamo. We assess the various energy sources available and estimate necessary lifetimes of the common envelope.

Subjects/Keywords: Stars; Astronomy; Rotation; Magnetic; Chemically peculiar; Evolution; Stellar

10 more images…

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Potter, A. T. (2012). Rotation and magnetism in massive stars. (Doctoral Dissertation). University of Cambridge. Retrieved from http://www.dspace.cam.ac.uk/handle/1810/243617https://www.repository.cam.ac.uk/bitstream/1810/243617/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/243617/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/243617/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/243617/9/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/7/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/10/potterThesis.pdf.jpg

Chicago Manual of Style (16^th Edition):

Potter, Adrian Thomas. “Rotation and magnetism in massive stars.” 2012. Doctoral Dissertation, University of Cambridge. Accessed March 08, 2021. http://www.dspace.cam.ac.uk/handle/1810/243617https://www.repository.cam.ac.uk/bitstream/1810/243617/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/243617/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/243617/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/243617/9/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/7/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/10/potterThesis.pdf.jpg.

MLA Handbook (7^th Edition):

Potter, Adrian Thomas. “Rotation and magnetism in massive stars.” 2012. Web. 08 Mar 2021.

Vancouver:

Potter AT. Rotation and magnetism in massive stars. [Internet] [Doctoral dissertation]. University of Cambridge; 2012. [cited 2021 Mar 08]. Available from: http://www.dspace.cam.ac.uk/handle/1810/243617https://www.repository.cam.ac.uk/bitstream/1810/243617/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/243617/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/243617/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/243617/9/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/7/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/10/potterThesis.pdf.jpg.

Council of Science Editors:

Potter AT. Rotation and magnetism in massive stars. [Doctoral Dissertation]. University of Cambridge; 2012. Available from: http://www.dspace.cam.ac.uk/handle/1810/243617https://www.repository.cam.ac.uk/bitstream/1810/243617/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/243617/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/243617/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/243617/9/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/7/potterThesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/243617/10/potterThesis.pdf.jpg

Open Access Theses and Dissertations