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Clemson University
1.
Tannous, Jaad Antoun.
The Effect of Rotation on Stellar Structure and Evolution.
Degree: MS, Physics and Astronomy, 2020, Clemson University
URL: https://tigerprints.clemson.edu/all_theses/3267 
► In this thesis, we investigate the eects of rotation on the evolution of stars in the mass range of 2-15 M assuming solar-like initial…
(more)
▼ In this thesis, we investigate the eects of
rotation on the evolution of stars
in the mass range of 2-15 M assuming solar-like initial composition. We have used
a well tested hydrodynamical
stellar evolution program [El Eid et al., 2009], which
has been extended to include a one-dimensional treatment of rotational instabilities.
The calculations for stars in the mass range up to 8 M have been performed
to include the Asymptotic Giant Branch (AGB) in order to gure out
whether rotational instabilities can eect the so called "third dredge up", leading
to a neutron source for the s-process nucleosynthesis.
In the case of massive stars, above 8 M, rotational eects are expected
to become important during the main sequence evolution, mainly owing to the
so called "Eddington-Sweet" circulation. An indication of the eect of
rotation
should show up through the surface enrichment of 4He and 14N at the end of
core Hydrogen burning. Another important aspect of
rotation is the study of
its eect on the shell carbon burning phase, where the s-process nucleosynthesis
occurs.[El Eid et al., 2000]
Advisors/Committee Members: Bradley S Meyer, Mounib F El-Eid, Dieter H Hartmann, Stephen R Kaeppler.
Subjects/Keywords: Rotation; s-process; Stellar Evolution; Stellar Structure
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APA (6th Edition):
Tannous, J. A. (2020). The Effect of Rotation on Stellar Structure and Evolution. (Masters Thesis). Clemson University. Retrieved from https://tigerprints.clemson.edu/all_theses/3267
Chicago Manual of Style (16th Edition):
Tannous, Jaad Antoun. “The Effect of Rotation on Stellar Structure and Evolution.” 2020. Masters Thesis, Clemson University. Accessed March 05, 2021.
https://tigerprints.clemson.edu/all_theses/3267.
MLA Handbook (7th Edition):
Tannous, Jaad Antoun. “The Effect of Rotation on Stellar Structure and Evolution.” 2020. Web. 05 Mar 2021.
Vancouver:
Tannous JA. The Effect of Rotation on Stellar Structure and Evolution. [Internet] [Masters thesis]. Clemson University; 2020. [cited 2021 Mar 05].
Available from: https://tigerprints.clemson.edu/all_theses/3267.
Council of Science Editors:
Tannous JA. The Effect of Rotation on Stellar Structure and Evolution. [Masters Thesis]. Clemson University; 2020. Available from: https://tigerprints.clemson.edu/all_theses/3267
University of Sydney
2.
Maestro, Vicente.
Interferometric observations of hot stars
.
Degree: 2014, University of Sydney
URL: http://hdl.handle.net/2123/11671
► Accurate determination of fundamental stellar properties is crucial in understanding and testing models of stellar structure and evolution. To date, most stars with independent determinations…
(more)
▼ Accurate determination of fundamental stellar properties is crucial in understanding and testing models of stellar structure and evolution. To date, most stars with independent determinations of stellar properties based on high-resolution observations by optical interferometers belong to stars of type F5 or later, and most of measurements for early type stars come almost exclusively from the seminal observations with the Narrabri Stellar Intensity Interferometer (NSII) 50 years ago. Additionally, stellar rotation, generally overlooked in standard stellar models for decades, can play a central role for early-type stars, given their frequent high rotation rates. In this case, determination of fundamental stellar properties requires accurate diameter estimates at a range of position angles, and a more detailed modelling of the stellar surface. Recent development of 2D stellar models including a self-consistent rotation description (incorporating differential rotation) in stars with radiative envelopes has provided a method to describe the effects of rotation that links them to fundamental properties,based on a small set of parameters determining the stellar structure (mass,composition,rotation). In this thesis I have determined fundamental stellar properties for 14 new stars with spectral types earlier than F6. For 10 of them, the effects of stellar rotation may be neglected, whereas the other 4 exhibit fast rotation. In order to derive stellar parameters for these stars, I have incorporated state-of-the-art 2D models into a code capable of generating a model synthesizing all observables into a robust and self-consistent framework. Using interferometry,star distances,photometry and spectroscopy in the ultraviolet,visible and infrared, the derived fundamental stellar parameters, together with rotation dependent evolutionary tracks,are used to determine mass and age of the stars,corrected for the bias induced by the star rotation axis orientation.
Subjects/Keywords: Optical Interferometry;
Stellar Astrophysics;
Stellar rotation
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APA (6th Edition):
Maestro, V. (2014). Interferometric observations of hot stars
. (Thesis). University of Sydney. Retrieved from http://hdl.handle.net/2123/11671
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Maestro, Vicente. “Interferometric observations of hot stars
.” 2014. Thesis, University of Sydney. Accessed March 05, 2021.
http://hdl.handle.net/2123/11671.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Maestro, Vicente. “Interferometric observations of hot stars
.” 2014. Web. 05 Mar 2021.
Vancouver:
Maestro V. Interferometric observations of hot stars
. [Internet] [Thesis]. University of Sydney; 2014. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/2123/11671.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Maestro V. Interferometric observations of hot stars
. [Thesis]. University of Sydney; 2014. Available from: http://hdl.handle.net/2123/11671
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Oxford
3.
McQuillan, Amy.
Stellar variability and rotation in Kepler planetary transit search data.
Degree: PhD, 2013, University of Oxford
URL: http://ora.ox.ac.uk/objects/uuid:802a873d-650f-4f0b-b814-f8397b2798e2
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618438
► The recent space-based exoplanet transit searches, CoRoT and Kepler, have revolutionised the field of stellar variability. In this thesis I exploit the public Kepler data…
(more)
▼ The recent space-based exoplanet transit searches, CoRoT and Kepler, have revolutionised the field of stellar variability. In this thesis I exploit the public Kepler data to characterise stellar variability, and study rotation periods. For the study of stellar variability it is a complicated but necessary process to remove instrumental systematics while maintaining intrinsic stellar signal. I was involved in the development of a new correction method for systematics, denoted ARC (Astrophysically Robust Correction). This method relies on the removal of a set of basis functions that are determined to be present in small amounts across many light curves. Using the first month of Kepler data, corrected with the ARC method, I studied the variability properties of main sequence stars as a function of fundamental stellar parameters. I find that the fraction of stars with variability greater than that of the Sun is 60%, and confirm the trend of increasing variability with decreasing effective temperatures. I show tentative evidence that the more active stars have lower proper motions and may be located closer to the galactic plane. I also investigate the frequency content of the variability, showing that there exist significant differences in the nature of variability between spectral types, with a trend towards longer periods at later spectral types. In order to exploit the full potential of the Kepler data for stellar rotation period measurement, I developed a novel method of period detection for use on star spot modulated light curves. Standard approaches to period detection are based on Fourier decomposition or least-squares fitting of sinusoidal models. However, typical stellar light curves are neither sinusoidal nor strictly periodic. Therefore, I developed an algorithm for period detection based on the autocorrelation function (ACF) of the light curve. Because the ACF measures only the degree of self-similarity of the light curve at a given time lag, the period remains detectable even when the amplitude and phase of the photometric modulation evolve significantly. I applied the ACF method for the sample of M-dwarfs observed during the first 10 months of the Kepler mission, and detected rotation periods in 1570, ranging from 0.37-69.7 days. The rotation period distribution is clearly bimodal, with peaks at ~19 and ~33 days, hinting at two distinct waves of star formation. These two peaks form two distinct sequences in period-temperature space, with the period decreasing with increasing temperature. In a natural continuation to this work I applied measured periods for 1000 stars in each of the F, G and K-dwarf sets observed by Kepler, and combined these with the M-dwarf results. The trend of increasing rotation period with increasing mass is clear throughout, as the observations fall along a wide by distinct sequence. Comparison to the rotational isochrones of Barnes (2007) show an overall agreement, although the dataset, which I believe is the largest set of rotation period measurements for main sequence stars, shows…
Subjects/Keywords: 523.8; Astrophysics; stellar physics; stellar rotation; stellar variability; systematics removal
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APA (6th Edition):
McQuillan, A. (2013). Stellar variability and rotation in Kepler planetary transit search data. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:802a873d-650f-4f0b-b814-f8397b2798e2 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618438
Chicago Manual of Style (16th Edition):
McQuillan, Amy. “Stellar variability and rotation in Kepler planetary transit search data.” 2013. Doctoral Dissertation, University of Oxford. Accessed March 05, 2021.
http://ora.ox.ac.uk/objects/uuid:802a873d-650f-4f0b-b814-f8397b2798e2 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618438.
MLA Handbook (7th Edition):
McQuillan, Amy. “Stellar variability and rotation in Kepler planetary transit search data.” 2013. Web. 05 Mar 2021.
Vancouver:
McQuillan A. Stellar variability and rotation in Kepler planetary transit search data. [Internet] [Doctoral dissertation]. University of Oxford; 2013. [cited 2021 Mar 05].
Available from: http://ora.ox.ac.uk/objects/uuid:802a873d-650f-4f0b-b814-f8397b2798e2 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618438.
Council of Science Editors:
McQuillan A. Stellar variability and rotation in Kepler planetary transit search data. [Doctoral Dissertation]. University of Oxford; 2013. Available from: http://ora.ox.ac.uk/objects/uuid:802a873d-650f-4f0b-b814-f8397b2798e2 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618438
4.
Mirouh, Giovanni Marcello.
Rôle de la rotation différentielle sur le spectre basse fréquence des étoiles en rotation rapide : Role of differential rotation on low-frequency oscillation spectra of fast-rotating stars.
Degree: Docteur es, Astrophysique, 2016, Université Toulouse III – Paul Sabatier
URL: http://www.theses.fr/2016TOU30374
► Les étoiles massives sont les principaux contributeurs à l'enrichissement du milieu interstellaire. Ce sont généralement des rotateurs rapides, dotés d'une enveloppe radiative dans laquelle l'interaction…
(more)
▼ Les étoiles massives sont les principaux contributeurs à l'enrichissement du milieu interstellaire. Ce sont généralement des rotateurs rapides, dotés d'une enveloppe radiative dans laquelle l'interaction de la stratification et la rotation génère une rotation différentielle. Celle-ci peut alimenter divers phénomènes de transport et l'évolution rapide de l'étoile. Nombre de ces étoiles sont par ailleurs des pulsateurs classiques. Cette thèse s'intéresse en premier lieu à l'interaction entre la rotation différentielle et les pulsations à basse fréquence dans l'étoile : celles-ci sont des modes gravito-inertiels dont la force de rappel est une combinaison de la force de Coriolis et de la poussée d'Archimède. Ils sondent les couches profondes de l'étoile, et sont étudiés suivant deux méthodes : dans la limite non-dissipative par la méthode des caractéristiques, et dans le cas dissipatif par la résolution du problème complet par une méthode spectrale. Nous mettons en évidence différentes singularités (attracteurs, latitudes critiques, résonances de corotation, piégeage en coin) et des modes réguliers. Certains modes sont excités par des instabilités baroclines, qui, si des effets non-linéaires provoquent leur saturation, permettent l'existence d'un mécanisme d'excitation nouveau dû à la rotation différentielle. Dans un second temps, nous avons associé le code de structure ESTER au code de calcul d'oscillations TOP. Ces deux codes calculent les quantités dans une étoile en deux dimensions et les modes associés en tenant compte des effets de la rotation de façon complète. Nous utilisons visibilités et taux d'amortissement des modes pour sélectionner dans le spectre synthétique les meilleurs candidats à l'identification des modes observés. Nous présentons une application au rotateur rapide Rasalhague (aOph), pour lequel de nombreuses observations sont disponibles. Nous n'avons pas obtenu une identification des modes univoque, mais le problème est maintenant mieux cerné et diverses pistes de progrès ont été identifiées.
Massive stars are the main contributors of the interstellar medium enrichment. These stars are usually fast rotators, with a radiative envelope in which the interaction between stratification and rotation gives rise to a differential rotation. This can trigger transport phenomena in the star, and affect its fast evolution. Besides, many of these stars are classical pulsators. This work focuses first on the impact of a differential rotation on the low-frequency oscillation spectrum which contains gravito-inertial modes. These modes are restored by the combination of buoyancy and Coriolis force and probe deep layers of stars. Our study is twofold : we compute the paths of characteristics in the non-dissipative limit, and solve the fully-dissipative eigenvalue problem numerically using a spectral decomposition. We find various singularities (attractors, critical latitudes, corotation resonances, wedge-trapping) and regular modes. Some of these modes are excited by baroclinic instabilities that may saturate…
Advisors/Committee Members: Rieutord, Michel (thesis director), Ballot, Jérôme (thesis director).
Subjects/Keywords: Etoiles; Oscillations stellaires; Etoiles en rotation; Rotation différentielle; Astérosismologie; Instabilités; Stars; Stellar pulsations; Stellar rotation; Differential rotation; Asteroseismology; Baroclinic instabilities
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APA ·
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APA (6th Edition):
Mirouh, G. M. (2016). Rôle de la rotation différentielle sur le spectre basse fréquence des étoiles en rotation rapide : Role of differential rotation on low-frequency oscillation spectra of fast-rotating stars. (Doctoral Dissertation). Université Toulouse III – Paul Sabatier. Retrieved from http://www.theses.fr/2016TOU30374
Chicago Manual of Style (16th Edition):
Mirouh, Giovanni Marcello. “Rôle de la rotation différentielle sur le spectre basse fréquence des étoiles en rotation rapide : Role of differential rotation on low-frequency oscillation spectra of fast-rotating stars.” 2016. Doctoral Dissertation, Université Toulouse III – Paul Sabatier. Accessed March 05, 2021.
http://www.theses.fr/2016TOU30374.
MLA Handbook (7th Edition):
Mirouh, Giovanni Marcello. “Rôle de la rotation différentielle sur le spectre basse fréquence des étoiles en rotation rapide : Role of differential rotation on low-frequency oscillation spectra of fast-rotating stars.” 2016. Web. 05 Mar 2021.
Vancouver:
Mirouh GM. Rôle de la rotation différentielle sur le spectre basse fréquence des étoiles en rotation rapide : Role of differential rotation on low-frequency oscillation spectra of fast-rotating stars. [Internet] [Doctoral dissertation]. Université Toulouse III – Paul Sabatier; 2016. [cited 2021 Mar 05].
Available from: http://www.theses.fr/2016TOU30374.
Council of Science Editors:
Mirouh GM. Rôle de la rotation différentielle sur le spectre basse fréquence des étoiles en rotation rapide : Role of differential rotation on low-frequency oscillation spectra of fast-rotating stars. [Doctoral Dissertation]. Université Toulouse III – Paul Sabatier; 2016. Available from: http://www.theses.fr/2016TOU30374
The Ohio State University
5.
Tayar, Jamie Nicole.
Rotation in Red Giants.
Degree: PhD, Astronomy, 2018, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1531927526281553
► Real stars rotate, and rotation can have profound consequences for stellar structure and evolution. Despite this, rotation is frequently ignored in evolved stars, or treated…
(more)
▼ Real stars rotate, and
rotation can have profound
consequences for
stellar structure and evolution. Despite this,
rotation is frequently ignored in evolved stars, or treated in a
highly simplified fashion. Previously, the surface and interior
rotation rates of low mass red giant stars were poorly constrained
and the uncertainty in the models could be marginalized over.
However, in an era of space-based photometry and large
spectroscopic surveys, it is now possible to measure the
rotation
rates of red giants, and to use these measurements to place novel
constraints on the physicsof these stars. In this dissertation, I
use the newly obtained large and precise asteroseismic and
spectroscopic data sets in comparison with
stellar models to better
understand red giant stars. I have identified important differences
between data and models for evolved stars. I have proposed
improvements to the fundamental temperature predictions of these
models, and then used the improved models to demonstrate that
current models do not adequate the rotational physics of these
stars. Using both surface and core
rotation rates and studying
trends in representative samples. I have demonstrated that the
coupling between the core and surface
rotation rates of evolved
stars are evolutionary state dependent, shown that a standard
Kawaler angular momentum loss law is insufficient for evolved
stars, found evidence for radial differential
rotation in the
convective zones of intermediate mass stars, calculatedthat the
timescales for rotational coupling of giants are long compared to
the pre-main-sequence, and placed a lower limit on the fraction of
stars that interact on the giant branch of 10%.
Advisors/Committee Members: Pinsonneault, Marc (Advisor).
Subjects/Keywords: Astronomy; stars; stellar evolution; stellar rotation; red giants
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APA (6th Edition):
Tayar, J. N. (2018). Rotation in Red Giants. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1531927526281553
Chicago Manual of Style (16th Edition):
Tayar, Jamie Nicole. “Rotation in Red Giants.” 2018. Doctoral Dissertation, The Ohio State University. Accessed March 05, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1531927526281553.
MLA Handbook (7th Edition):
Tayar, Jamie Nicole. “Rotation in Red Giants.” 2018. Web. 05 Mar 2021.
Vancouver:
Tayar JN. Rotation in Red Giants. [Internet] [Doctoral dissertation]. The Ohio State University; 2018. [cited 2021 Mar 05].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1531927526281553.
Council of Science Editors:
Tayar JN. Rotation in Red Giants. [Doctoral Dissertation]. The Ohio State University; 2018. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1531927526281553
6.
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
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APA ·
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APA (6th 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 (16th 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 05, 2021.
http://www.theses.fr/2016MONTT258.
MLA Handbook (7th Edition):
Amard, Louis. “Évolution de la rotation des étoiles jeunes de faible masse : Rotational evolution of young low-mass stars.” 2016. Web. 05 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 05].
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
7.
Jendreieck, Andressa Maria.
Sismologia e Rotação ao Longo da Sequência Principal.
Degree: Mestrado, Astronomia, 2011, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/14/14131/tde-27042011-164107/
;
► A sismologia estelar oferece uma oportunidade única de sondar as propriedades internas das estrelas através do estudo de oscilações estelares. Essas oscilações são dependentes diretamente…
(more)
▼ A sismologia estelar oferece uma oportunidade única de sondar as propriedades internas das estrelas através do estudo de oscilações estelares. Essas oscilações são dependentes diretamente da física da cavidade onde são formadas. No entanto, a rotação da estrela introduz um eixo de simetria e levanta a degenerescência nas frequências, dificultando assim, a sua identificação. O objetivo deste trabalho foi estudar a dependência das frequências de oscilação estelar com a velocidade de rotação para modelos de massas intermediárias ao longo da sequência principal. Este estudo foi realizado através da modelagem de estrelas com uma grande variedade de massas e velocidades de rotação (2-8 Msol, 20-100km/s) com os códigos CESAM/FILOU. O comportamento do splitting rotacional e de sua assimetria nos modos g2, g1, p1 e p2 mostrou uma dependência com outros parâmetros físicos, além da rotação. A assimetria apresenta variações interessantes levando a um método de diagnóstico de evolução: quando vários modos são observados, as assimetrias levam a uma determinação precisa da fase evolutiva da estrela. Modelos representativos para a estrela HD50844 foram comparados com os dados observacionais. A falta da identificação dos modos (l,m) e o grande número de frequências não permite obter-se resultados precisos.
Asteroseismology provides a unique opportunity to probe the inner properties of stars through the study of stellar oscillations. These oscillations depend on the physics of the cavity where they are formed. However, the stellar rotation introduces an axis of symmetry and lifts the degeneracy of the frequencies, thus hindering the identification. The goal of this work was to study the dependence of the oscillation frequency on the stellar rotation velocities for models of intermediate mass along the main sequence. This study was performed through the modeling of stars with a wide range of masses and rotational velocities (2-8 Msun, 20-100km/s) with the codes CESAM/FILOU. The behavior of the rotational \it and its asymmetry for the modes g2, g1, p1 and p2 showed a dependence on other physical parameters, as well as rotation. The asymmetry presents interesting variations leading to a diagnostic method of evolution: when multiple modes are observed, the asymmetries lead to a precise determination of the evolution phase of the star. Representative models for the star HD50844 were compared with the observational data. The lack of identification of the modes (l,m) and the large number of frequencies does not allow to obtain accurate results.
Advisors/Committee Members: Pacheco, Eduardo Janot.
Subjects/Keywords: Asteroseismology; modelos oscilatórios.; Oscillatory Models.; rotação estelar; Sismologia estelar; Stellar Rotation
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Manager
APA (6th Edition):
Jendreieck, A. M. (2011). Sismologia e Rotação ao Longo da Sequência Principal. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/14/14131/tde-27042011-164107/ ;
Chicago Manual of Style (16th Edition):
Jendreieck, Andressa Maria. “Sismologia e Rotação ao Longo da Sequência Principal.” 2011. Masters Thesis, University of São Paulo. Accessed March 05, 2021.
http://www.teses.usp.br/teses/disponiveis/14/14131/tde-27042011-164107/ ;.
MLA Handbook (7th Edition):
Jendreieck, Andressa Maria. “Sismologia e Rotação ao Longo da Sequência Principal.” 2011. Web. 05 Mar 2021.
Vancouver:
Jendreieck AM. Sismologia e Rotação ao Longo da Sequência Principal. [Internet] [Masters thesis]. University of São Paulo; 2011. [cited 2021 Mar 05].
Available from: http://www.teses.usp.br/teses/disponiveis/14/14131/tde-27042011-164107/ ;.
Council of Science Editors:
Jendreieck AM. Sismologia e Rotação ao Longo da Sequência Principal. [Masters Thesis]. University of São Paulo; 2011. Available from: http://www.teses.usp.br/teses/disponiveis/14/14131/tde-27042011-164107/ ;
8.
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 109G. 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
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Chicago ·
MLA ·
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APA (6th 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 (16th Edition):
Potter, Adrian Thomas. “Rotation and magnetism in massive stars.” 2012. Doctoral Dissertation, University of Cambridge. Accessed March 05, 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 (7th Edition):
Potter, Adrian Thomas. “Rotation and magnetism in massive stars.” 2012. Web. 05 Mar 2021.
Vancouver:
Potter AT. Rotation and magnetism in massive stars. [Internet] [Doctoral dissertation]. University of Cambridge; 2012. [cited 2021 Mar 05].
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
9.
Zayer, Imad.
Searching for Rotational and Activity Signals in M Dwarf Stars.
Degree: 2017, University of Hertfordshire
URL: http://hdl.handle.net/2299/18729
► We search for signals coming from M dwarf stars through variations caused by stellar surface activity. The aims of this work are to find the…
(more)
▼ We search for signals coming from M dwarf stars through variations caused by stellar
surface activity.
The aims of this work are to find the stellar rotation period of M dwarf stars and check
them against known planetary signals. We used photometric ASAS data for 36 M dwarf
stars with literature rotation periods. We used our own noise filtering code and the
Systemic Console program to identify the significant signals. In addition, we investigate
the correlation between the M dwarf rotation and chromospheric emission, represented
by H and CaII H&K lines.
This research has provided valuable information regarding how to identify correct stellar
rotation periods. We show a good agreement between our photometric rotation periods
and corresponding photometric periods in the literature. On the other hand we only
find agreement for 8 out of 20 targets where a spectroscopic rotation periods is in the
literature. We confirm that several planetary signals of candidate planets reported in
the literature are very different to the stellar rotation periods of host stars. For early
M dwarfs with periods of less than 40 days we find a relationship between the level of
activity as measured by H and CaII H&K lines and the photometric rotation period.
Subjects/Keywords: exoplanet; rotation periods; M dwarfs; stellar activity; aliases; periodogram; ASAS photometric
Record Details
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zayer, I. (2017). Searching for Rotational and Activity Signals in M Dwarf Stars. (Masters Thesis). University of Hertfordshire. Retrieved from http://hdl.handle.net/2299/18729
Chicago Manual of Style (16th Edition):
Zayer, Imad. “Searching for Rotational and Activity Signals in M Dwarf Stars.” 2017. Masters Thesis, University of Hertfordshire. Accessed March 05, 2021.
http://hdl.handle.net/2299/18729.
MLA Handbook (7th Edition):
Zayer, Imad. “Searching for Rotational and Activity Signals in M Dwarf Stars.” 2017. Web. 05 Mar 2021.
Vancouver:
Zayer I. Searching for Rotational and Activity Signals in M Dwarf Stars. [Internet] [Masters thesis]. University of Hertfordshire; 2017. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/2299/18729.
Council of Science Editors:
Zayer I. Searching for Rotational and Activity Signals in M Dwarf Stars. [Masters Thesis]. University of Hertfordshire; 2017. Available from: http://hdl.handle.net/2299/18729
University of Cambridge
10.
Potter, Adrian Thomas.
Rotation and magnetism in massive stars.
Degree: PhD, 2012, University of Cambridge
URL: https://doi.org/10.17863/CAM.15999
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556241
► 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: 520; Stars; Astronomy; Rotation; Magnetic; Chemically peculiar; Evolution; Stellar
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Potter, A. T. (2012). Rotation and magnetism in massive stars. (Doctoral Dissertation). University of Cambridge. Retrieved from https://doi.org/10.17863/CAM.15999 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556241
Chicago Manual of Style (16th Edition):
Potter, Adrian Thomas. “Rotation and magnetism in massive stars.” 2012. Doctoral Dissertation, University of Cambridge. Accessed March 05, 2021.
https://doi.org/10.17863/CAM.15999 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556241.
MLA Handbook (7th Edition):
Potter, Adrian Thomas. “Rotation and magnetism in massive stars.” 2012. Web. 05 Mar 2021.
Vancouver:
Potter AT. Rotation and magnetism in massive stars. [Internet] [Doctoral dissertation]. University of Cambridge; 2012. [cited 2021 Mar 05].
Available from: https://doi.org/10.17863/CAM.15999 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556241.
Council of Science Editors:
Potter AT. Rotation and magnetism in massive stars. [Doctoral Dissertation]. University of Cambridge; 2012. Available from: https://doi.org/10.17863/CAM.15999 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556241
University of Sydney
11.
Li, Gang.
Asteroseismology of gamma Doradus stars with Kepler
.
Degree: 2020, University of Sydney
URL: http://hdl.handle.net/2123/23393
► Stellar physics is a vital part of modern astronomy. To better understand stars, we must understand not only the stellar surface, but also the stellar…
(more)
▼ Stellar physics is a vital part of modern astronomy. To better understand stars, we must understand not only the stellar surface, but also the stellar interior. We can use the waves propagating in stars to probe stellar inner regions. Asteroseismology, the science that investigates the stellar waves, has been an effective tool to research stellar interiors. I conducted an observational study of the gamma Doradus stars using data from NASA's Kepler mission. These stars have masses between 1.4 and 2.0 solar masses and pulsate mainly in gravity and Rossby modes, showing period spacing patterns in the Fourier spectra. The pulsations are sensitive to the stellar structure near the upper boundary of the convective core, hence they are valuable for understanding the stellar interior. I identified period spacing patterns in more than 600 gamma Dor stars from the 4-yr Kepler data, which allowed me to measure the asymptotic spacings, the near-core rotation rates, and the radial orders. My results show that the stars rotate more slowly than predicted by the theory, and the rotation distribution shows excess at the slow-rotation side for unclear reasons. I also detected the core-to-surface rotation profiles in about 10% stars. The interiors rotate faster than the cores in most stars, but by no more than 5%. I applied my methods to the gamma Dor stars in eclipsing binaries, and compared the near-core rotation periods with the orbital periods. The results show that a star is more likely to be tidally locked if its orbital period is shorter than about 10 days. More slow rotators are seen in the eclipsing binary sample, which might be an explanation of the slow-rotator excess mentioned in the previous paragraph. Several stars have extremely slow core rotation with the orbital periods longer than 100 days, implying a new mechanism interacting between the tidal forces and the g-mode pulsations.
Subjects/Keywords: Asteroseismology;
stellar rotation;
gamma Doradus stars;
eclipsing binaries
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, G. (2020). Asteroseismology of gamma Doradus stars with Kepler
. (Thesis). University of Sydney. Retrieved from http://hdl.handle.net/2123/23393
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Li, Gang. “Asteroseismology of gamma Doradus stars with Kepler
.” 2020. Thesis, University of Sydney. Accessed March 05, 2021.
http://hdl.handle.net/2123/23393.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Li, Gang. “Asteroseismology of gamma Doradus stars with Kepler
.” 2020. Web. 05 Mar 2021.
Vancouver:
Li G. Asteroseismology of gamma Doradus stars with Kepler
. [Internet] [Thesis]. University of Sydney; 2020. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/2123/23393.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Li G. Asteroseismology of gamma Doradus stars with Kepler
. [Thesis]. University of Sydney; 2020. Available from: http://hdl.handle.net/2123/23393
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
12.
Taiza Alissul Sauer do Carmo.
Espectroscopia de Estrelas Be nos aglomerados NGC 4755 e NGC 6530.
Degree: 2008, UNIVERSIDADE ESTADUAL DE PONTA GROSSA
URL: http://www.bicen-tede.uepg.br/tde_busca/arquivo.php?codArquivo=174
► Uma das principais teorias para explicar o fenômeno Be é que são estrelas quentes com velocidade de rotação próxima da velocidade crítica, ejetando matéria formando…
(more)
▼ Uma das principais teorias para explicar o fenômeno Be é que são estrelas quentes com velocidade de rotação próxima da velocidade crítica, ejetando matéria formando um disco gasoso ao seu redor. Sua geometria e cinemática ainda é um assunto calorosamente discutido. Esses objetos apresentam emissões nas linhas de Balmer, entre outros fenômenos. Neste trabalho são apresentadas observações de estrelas quentes em aglomerados jovens abertos e a detecção de Be nestes. O estudo de estrelas Be em aglomerados abertos é de particular interesse porque estes objetos guardam as assinaturas das condições iniciais de sua formação. A maioria das estrelas Be conhecidas em aglomerados abertos foram identificadas na Via Láctea, a maioria das observações concentra-se em procurar as linhas em emissão características nas estrelas de baixa magnitude. Como conseqüência a completeza de incidência de estrelas Be em aglomerados abertos é incerta, o que leva a um estímulo para o seu estudo. Nesse trabalho, foram estudadas trinta e duas estrelas do tipo espectral B, selecionadas dos aglomerados NGC 4755 e NGC 6530. Em uma primeira etapa, foi realizada uma análise das estrelas que apresentam o fenômeno Be. Depois, foram determinados os parâmetros físicos de estrelas B e Be utilizando as linhas de HeI 4471 e MgII 4481 Å. Foi realizada, ainda, uma comparação entre os valores de vseni calculados com o algoritmo AMOEBA e os valores obtidos com os programas elaborados no IDL. Para altas velocidades ( 300 Km/s), há superestimativas do método FWHM, para ambos os aglomerados. Mas para baixas velocidades, há consistência entre os valores de vseni obtidos com o método FWHM e AMOEBA.
One of the main theories to explain the Be phenomenon is that they are hot stars with rotation speed close to the critical limit, ejecting matter and forming a gaseous disk around. Its geometry and kinematics is still a controversial subject. Those objects present H line in emission among other phenomena. In this work are present observations of hot stars in young open clusters and the detection of Be stars. The study of Be stars in open clusters is a matter of interest because these objects keep the initial signatures of their initial formation. Most of Be stars known in open clusters were identified inside the Milky Way Galaxy, but not all were observed. Most of the observations concentrate on seeking the characteristics lines in emission for stars with low magnitude. As a consequence the complete scenario of incidence of Be stars in open clusters is still uncertain, what incentives its observation. In this work, we studied thirty two stars of the spectral type B, from NGC 4755 and NGC 6530 stellar clusters. As a first step we accomplished an analysis of the stars that present the Be phenomenon. Than, we estimate physical parameters of B and Be stars using the lines of HeI 4471 and MgII 4481 Å. We also accomplished a comparison among the vseni values calculated by several methods including the AMOEBA algorithm and other two methods elaborated using the IDL platform. For…
Advisors/Committee Members: Eduardo Janot Pacheco, Ronaldo Savarino Levenhagen, Marcelo Emilio.
Subjects/Keywords: espectroscopia estelar; estrelas Be; linhas de Balmer; rotação estelar; stellar spectroscopy; Be stars; Balmer lines; stellar rotation; FISICA
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Carmo, T. A. S. d. (2008). Espectroscopia de Estrelas Be nos aglomerados NGC 4755 e NGC 6530. (Thesis). UNIVERSIDADE ESTADUAL DE PONTA GROSSA. Retrieved from http://www.bicen-tede.uepg.br/tde_busca/arquivo.php?codArquivo=174
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Carmo, Taiza Alissul Sauer do. “Espectroscopia de Estrelas Be nos aglomerados NGC 4755 e NGC 6530.” 2008. Thesis, UNIVERSIDADE ESTADUAL DE PONTA GROSSA. Accessed March 05, 2021.
http://www.bicen-tede.uepg.br/tde_busca/arquivo.php?codArquivo=174.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Carmo, Taiza Alissul Sauer do. “Espectroscopia de Estrelas Be nos aglomerados NGC 4755 e NGC 6530.” 2008. Web. 05 Mar 2021.
Vancouver:
Carmo TASd. Espectroscopia de Estrelas Be nos aglomerados NGC 4755 e NGC 6530. [Internet] [Thesis]. UNIVERSIDADE ESTADUAL DE PONTA GROSSA; 2008. [cited 2021 Mar 05].
Available from: http://www.bicen-tede.uepg.br/tde_busca/arquivo.php?codArquivo=174.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Carmo TASd. Espectroscopia de Estrelas Be nos aglomerados NGC 4755 e NGC 6530. [Thesis]. UNIVERSIDADE ESTADUAL DE PONTA GROSSA; 2008. Available from: http://www.bicen-tede.uepg.br/tde_busca/arquivo.php?codArquivo=174
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
13.
Notsu, Yuta.
Observational studies on solar-type superflare stars
.
Degree: 2019, Kyoto University
URL: http://hdl.handle.net/2433/242613
Subjects/Keywords: stellar flare;
superflare;
starspot;
solar-type stars;
stellar rotation
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Notsu, Y. (2019). Observational studies on solar-type superflare stars
. (Thesis). Kyoto University. Retrieved from http://hdl.handle.net/2433/242613
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Notsu, Yuta. “Observational studies on solar-type superflare stars
.” 2019. Thesis, Kyoto University. Accessed March 05, 2021.
http://hdl.handle.net/2433/242613.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Notsu, Yuta. “Observational studies on solar-type superflare stars
.” 2019. Web. 05 Mar 2021.
Vancouver:
Notsu Y. Observational studies on solar-type superflare stars
. [Internet] [Thesis]. Kyoto University; 2019. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/2433/242613.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Notsu Y. Observational studies on solar-type superflare stars
. [Thesis]. Kyoto University; 2019. Available from: http://hdl.handle.net/2433/242613
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
14.
van Saders, Jennifer Lynn.
Using Modern Stellar Observables to Constrain Stellar
Parameters and the Physics of the Stellar Interior.
Degree: PhD, Astronomy, 2014, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1404130939
► The current state and future evolution of a star is, in principle, specified by a only a few physical quantities: the mass, age, hydrogen, helium,…
(more)
▼ The current state and future evolution of a star is,
in principle, specified by a only a few physical quantities: the
mass, age, hydrogen, helium, and metal abundance. These same
fundamental quantities are crucial for reconstructing the history
of
stellar systems ranging in scale from planetary systems to
galaxies. However, the fundamental parameters are rarely directly
observable, and we are forced to use proxies that are not always
sensitive or unique functions of the
stellar parameters we wish to
determine. Imprecise or inaccurate determinations of the
fundamental parameters often limit our ability to draw inferences
about a given system. As new technologies, instruments, and
observing techniques become available, the list of viable
stellar
observables increases, and we can explore new links between the
observables and fundamental quantities in an effort to better
characterize
stellar systems. In the era of missions such as
Kepler, time-domain observables such as the
stellar rotation period and
stellar oscillations are now available
for an unprecedented number of stars, and future missions promise
to further expand the sample. Furthermore, despite the successes of
stellar evolution models, the processes and detailed structure of
the deep
stellar interior remains uncertain. Even in the case of
well-measured, well understood
stellar observables, the link to the
underlying parameters contains uncertainties due to our imperfect
understanding of
stellar interiors. Model uncertainties arise from
sources such as the treatment of turbulent convection, transport of
angular momentum and mixing, and assumptions about the physical
conditions of
stellar matter. By carefully examining the
sensitivity of
stellar observables to physical processes operating
within the star and model assumptions, we can design observational
tests for the theory of
stellar interiors. I propose a series of
tools based on new or revisited
stellar observables that can be
used both to constrain
stellar parameters and the physics of the
interior. I examine how the acoustic signature of the location of
the base of
stellar convective envelopes can be used as an absolute
abundance indicator, and describe a novel
3He-burning instability in low mass stars
along with the observational signatures of such a process. Finally,
I examine the manner in which
stellar rotation, observed in a
population of objects, can be used as a means to distinguish
between different evolutionary states, masses, and ages. I
emphasize that
rotation periods can be used as age indicators (as
often discussed in the literature), but that the interpretation of
rotation periods must be made within the context of the full
stellar population to arrive at accurate results.
Advisors/Committee Members: Pinsonneault, Marc (Advisor).
Subjects/Keywords: Astrophysics; Astronomy; stars; stellar evolution; stellar rotation; asteroseismology; stellar structure
…Star; Old Star,
Young Star: Subgiant Rotation as a Population and Stellar Physics Diagnostic… …Asteroseismology . . . . . . . . . . . . . . . . .
5
1.4
Modern Observables: Stellar Rotation… …of Model Predictions with Observations . . . . . .
98
Stellar Rotation as a Tool… …inertia for a range of stellar masses. . . . . . . . . . . 122
4.2
Theoretical rotation… …constrain stellar parameters and interiors.
1.4. Modern Observables: Stellar Rotation
All stars…
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APA (6th Edition):
van Saders, J. L. (2014). Using Modern Stellar Observables to Constrain Stellar
Parameters and the Physics of the Stellar Interior. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1404130939
Chicago Manual of Style (16th Edition):
van Saders, Jennifer Lynn. “Using Modern Stellar Observables to Constrain Stellar
Parameters and the Physics of the Stellar Interior.” 2014. Doctoral Dissertation, The Ohio State University. Accessed March 05, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1404130939.
MLA Handbook (7th Edition):
van Saders, Jennifer Lynn. “Using Modern Stellar Observables to Constrain Stellar
Parameters and the Physics of the Stellar Interior.” 2014. Web. 05 Mar 2021.
Vancouver:
van Saders JL. Using Modern Stellar Observables to Constrain Stellar
Parameters and the Physics of the Stellar Interior. [Internet] [Doctoral dissertation]. The Ohio State University; 2014. [cited 2021 Mar 05].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1404130939.
Council of Science Editors:
van Saders JL. Using Modern Stellar Observables to Constrain Stellar
Parameters and the Physics of the Stellar Interior. [Doctoral Dissertation]. The Ohio State University; 2014. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1404130939
15.
Junqueira, Thiago Correr.
Determinação da curva de rotação galática e estudo do mínimo próximo a R0.
Degree: Mestrado, Astronomia, 2009, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/14/14131/tde-10092009-125714/
;
► A curva de rotação da Galáxia apresenta uma anomalia perto do raio da órbita solar R0, caracterizada pela presença de um mínimo. Existem trabalhos que,…
(more)
▼ A curva de rotação da Galáxia apresenta uma anomalia perto do raio da órbita solar R0, caracterizada pela presença de um mínimo. Existem trabalhos que, embora não façam uma afirmação categórica, interpretam o mínimo como sendo o resultado do decréscimo do efeito do disco, combinado com o aumento do efeito de um hipotético halo de matéria escura. A existência de tal interpretação reforça a importância de um estudo detalhado sobre sua natureza. No presente trabalho nós mapeamos a curva de rotação entre os raios galáticos 5 < R < 12 kpc usando diversas estrelas como traçadoras, por exemplo, Cefeidas, C-Miras, etc. Através de um método original realizamos o estudo cinemático para 322 Cefeidas. A partir desse estudo determinamos os melhores valores para os parâmetros da Galáxia, V0=202 +- 15 km/s e R0=7.5 +- 0.5 kpc. A melhor escolha possível para tais parâmetros é de fundamental importância, pois estes afetam a curva de rotação deduzida a partir de dados observacionais. Após determinarmos os valores de R0 e V0, analisamos as curvas de rotação obtidas por nós e vimos que elas apresentam um mínimo a uma distância de 1.5 +- 0.3 kpc de R0. O mínimo apresenta uma velocidade de 30 +- 10 km/s menor que a velocidade encontrada no raio galático igual a R0. Simulações computacionais mostraram que esse mínimo pode ser explicado por um déficit gaussiano na densidade superficial de matéria (gás + estrelas) do disco, com um decréscimo máximo de 30% do valor da densidade superficial total próxima a R0. Esse déficit pode ser explicado pelo efeito da co-rotação.
The Galaxy rotation curve shows an anomaly near the solar radius orbit R0, characterized by the presence of a minimum. There are works that implicitly interpret the minimum as the result of the decrease of the effect of the disk, combined with increasing of effect of a hypothetical dark matter halo. The existence of this interpretation reinforces the importance of a detailed study about its nature. In this work we obtained the rotation curve between Galactic radius, 5 < R < 12 kpc, using several stars as tracers, for instance, Cepheids, C-Miras, etc. Through a new method, we studied the kinematic of 322 Cepheids. From this study we determined the best values for the Galaxy parameters, V0=202 +- 15 km/s, and R0=7.5 +- 0.5 kpc. The best possible choice for such parameters is of fundamental importance since they affect the rotation curve inferred from observational data. After determining the values of R0, and V0, we analyzed the rotation curves obtained by us, and we saw that they have a minimum at a distance of 1.5 +- 0.3 kpc from R0. The minimum shows a velocity of 30 +- 10 km/s less than the velocity found at galactic radius R0. Computational simulations showed that this minimum can be explained by a Gaussian deficit of surface density of matter (gas + stars) of disk, with a maximum decrease of 30% of the value of surface density total arround R0. This deficit is explained by the effect of co-rotation.
Advisors/Committee Members: Lepine, Jacques Raymond Daniel.
Subjects/Keywords: Cinemática Estelar; Curva de Rotação; Estrutura da Galáxia; galactic constant measurements.; Rotation curve; stellar kinematics
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APA ·
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MLA ·
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to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Junqueira, T. C. (2009). Determinação da curva de rotação galática e estudo do mínimo próximo a R0. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/14/14131/tde-10092009-125714/ ;
Chicago Manual of Style (16th Edition):
Junqueira, Thiago Correr. “Determinação da curva de rotação galática e estudo do mínimo próximo a R0.” 2009. Masters Thesis, University of São Paulo. Accessed March 05, 2021.
http://www.teses.usp.br/teses/disponiveis/14/14131/tde-10092009-125714/ ;.
MLA Handbook (7th Edition):
Junqueira, Thiago Correr. “Determinação da curva de rotação galática e estudo do mínimo próximo a R0.” 2009. Web. 05 Mar 2021.
Vancouver:
Junqueira TC. Determinação da curva de rotação galática e estudo do mínimo próximo a R0. [Internet] [Masters thesis]. University of São Paulo; 2009. [cited 2021 Mar 05].
Available from: http://www.teses.usp.br/teses/disponiveis/14/14131/tde-10092009-125714/ ;.
Council of Science Editors:
Junqueira TC. Determinação da curva de rotação galática e estudo do mínimo próximo a R0. [Masters Thesis]. University of São Paulo; 2009. Available from: http://www.teses.usp.br/teses/disponiveis/14/14131/tde-10092009-125714/ ;
Universidade do Rio Grande do Norte
16.
Nascimento, Sanzia Alves do.
Propriedades físicas de planetas extrasolares
.
Degree: 2008, Universidade do Rio Grande do Norte
URL: http://repositorio.ufrn.br/handle/123456789/18579
► ROTATION is one the most important aspects to be observed in stellar astrophysics. Here we investigate that particularly in stars with planets. This physical parameter…
(more)
▼ ROTATION is one the most important aspects to be observed in
stellar astrophysics. Here we investigate that particularly in stars with planets. This physical parameter supplies information about the distribution of angular momentum in the planetary system, as well as its role on the control of dierent phenomena, including coronal and cromospherical emission and on the ones due of tidal effects. In spite of the continuous solid advances made on the study of the characteristics and properties of planet host stars, the main features of their rotational behavior is are not well established yet. In this context, the present work brings an unprecedented study about the
rotation and angular
momentum of planet-harbouring stars, as well as the correlation between
rotation and
stellar and planetary physical properties. Our analysis is based on a sample of 232 extrasolar planets, orbiting 196 stars of dierent luminosity classes and spectral types. In addition to the study of their rotational behavior, the behavior of the physical properties
of stars and their orbiting planets was also analyzed, including
stellar mass and metallicity, as well as the planetary orbital parameters. As main results we can underline that the
rotation of stars with planets present two clear features: stars with Tef lower than about 6000 K have slower rotations, while among stars with Tef > 6000 K we and moderate
and fast rotations, though there are a few exceptions. We also show that stars with planets follow mostly the Krafts law, namely < J > / v rot. In this same idea we show
that the
rotation versus age relation of stars with planets follows, at least qualitatively, the Skumanich and Pace & Pasquini laws. The relation
rotation versus orbital period
also points for a very interesting result, with planet-harbouring stars with shorter orbital periods present rather enhanced
rotation
Advisors/Committee Members: Medeiros, José Renan de (advisor), CPF:08896135400 (advisor), http://lattes.cnpq.br/9151590034650501 (advisor).
Subjects/Keywords: Rotação estelar;
Exoplanetas;
Momento angular;
Estrelas hospedeiras;
Parâmetros físicos;
Stellar rotation;
Exoplanets;
Angular momentum;
Stars with planets;
Physical parameter
Record Details
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Share »
Record Details
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« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Nascimento, S. A. d. (2008). Propriedades físicas de planetas extrasolares
. (Thesis). Universidade do Rio Grande do Norte. Retrieved from http://repositorio.ufrn.br/handle/123456789/18579
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Nascimento, Sanzia Alves do. “Propriedades físicas de planetas extrasolares
.” 2008. Thesis, Universidade do Rio Grande do Norte. Accessed March 05, 2021.
http://repositorio.ufrn.br/handle/123456789/18579.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nascimento, Sanzia Alves do. “Propriedades físicas de planetas extrasolares
.” 2008. Web. 05 Mar 2021.
Vancouver:
Nascimento SAd. Propriedades físicas de planetas extrasolares
. [Internet] [Thesis]. Universidade do Rio Grande do Norte; 2008. [cited 2021 Mar 05].
Available from: http://repositorio.ufrn.br/handle/123456789/18579.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nascimento SAd. Propriedades físicas de planetas extrasolares
. [Thesis]. Universidade do Rio Grande do Norte; 2008. Available from: http://repositorio.ufrn.br/handle/123456789/18579
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
17.
Sanzia Alves do Nascimento.
Propriedades físicas de planetas extrasolares.
Degree: 2008, Universidade Federal do Rio Grande do Norte
URL: http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=2027
► ROTAÇÃO é um dos importantes aspectos a ser observado na astrofísica estelar. Por isto, neste trabalho, investigamos este parâmetro no estudo das estrelas hospedeiras de…
(more)
▼ ROTAÇÃO é um dos importantes aspectos a ser observado na astrofísica estelar. Por isto, neste trabalho, investigamos este parâmetro no estudo das estrelas hospedeiras de planetas. Parâmetro físico este que fornece informação sobre a distribuição do momentum angular dos sistemas planetários, bem como sobre o seu papel nos mais diferentes fenômenos, incluindo emissão cromosférica e coronal e sobre aqueles decorrentes de efeitos de maré. Apesar dos contínuos avanços feitos no estudo das características e das propriedades destes objetos, as principais características de seu comportamento rotatório ainda não estão bem estabelecidas. Neste contexto, o presente trabalho traz um estudo pioneiro sobre a rotação e o momentum angular das estrelas hospedeiras de planetas, bem como sobre a correlação entre rotação e parâmetros físicos estelares e planetários. Nossa análise é baseada em uma amostra de 232 planetas extrasolares, orbitando 196 estrelas de diferentes classes de luminosidade e tipos espectrais. Além do estudo do comportamento rotacional dessas estrelas, re-visitamos o comportamento das propriedades físicas destas estrelas e de seus planetas, incluindo a massa estelar e a metalicidade, bem como os parâmetros orbitais planetários. Como resultados principais, podemos sublinhar que a rotação das estrelas com planetas apresenta duas claras características: estrelas com Tef inferiores a proximadamente 6000 K possuem rotações mais baixas, enquanto que entre aquelas com Tef >6000 K encontramos rotações modv eradas e altas, embora algumas exceções. Nós mostramos também que as estrelas com planetas seguem, em sua maioria, a lei do Kraft, a saber <J >/ v rot. Nesta mesma linha nós mostramos que a relação rotação versus idade das estrelas com planetas segue, ao menos qualitativamente, como qualquer outra estrela de campo ou de aglomerado, a lei de Skumanich e de Pace &Pasquini. Um resultado interessante a ser destacado é a relação rotação versus período orbital, que aponta para uma tendência de que as estrelas que abrigam planetas com período orbital menores apresentam rotações mais realçadas
ROTATION is one the most important aspects to be observed in stellar astrophysics. Here we investigate that particularly in stars with planets. This physical parameter supplies information about the distribution of angular momentum in the planetary system, as well as its role on the control of dierent phenomena, including coronal and cromospherical emission and on the ones due of tidal effects. In spite of the continuous solid advances made on the study of the characteristics and properties of planet host stars, the main features of their rotational behavior is are not well established yet. In this context, the present work brings an unprecedented study about the rotation and angular momentum of planet-harbouring stars, as well as the correlation between rotation and stellar and planetary physical properties. Our analysis is based on a sample of 232 extrasolar planets, orbiting 196 stars of dierent luminosity classes and spectral types.…
Advisors/Committee Members: José Renan de Medeiros, José Dias do Nascimento Júnior, Bruno Leonardo Canto Martins.
Subjects/Keywords: Rotação estelar; Exoplanetas; Momento angular; Estrelas hospedeiras; Parâmetros físicos; ASTROFISICA ESTELAR; Stellar rotation; Exoplanets; Angular momentum; Stars with planets; Physical parameter
Record Details
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Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Nascimento, S. A. d. (2008). Propriedades físicas de planetas extrasolares. (Thesis). Universidade Federal do Rio Grande do Norte. Retrieved from http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=2027
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Nascimento, Sanzia Alves do. “Propriedades físicas de planetas extrasolares.” 2008. Thesis, Universidade Federal do Rio Grande do Norte. Accessed March 05, 2021.
http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=2027.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nascimento, Sanzia Alves do. “Propriedades físicas de planetas extrasolares.” 2008. Web. 05 Mar 2021.
Vancouver:
Nascimento SAd. Propriedades físicas de planetas extrasolares. [Internet] [Thesis]. Universidade Federal do Rio Grande do Norte; 2008. [cited 2021 Mar 05].
Available from: http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=2027.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nascimento SAd. Propriedades físicas de planetas extrasolares. [Thesis]. Universidade Federal do Rio Grande do Norte; 2008. Available from: http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=2027
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Universidade do Rio Grande do Norte
18.
Nascimento, Sanzia Alves do.
Propriedades físicas de planetas extrasolares
.
Degree: 2008, Universidade do Rio Grande do Norte
URL: http://repositorio.ufrn.br/handle/123456789/18579
► ROTATION is one the most important aspects to be observed in stellar astrophysics. Here we investigate that particularly in stars with planets. This physical parameter…
(more)
▼ ROTATION is one the most important aspects to be observed in
stellar astrophysics. Here we investigate that particularly in stars with planets. This physical parameter supplies information about the distribution of angular momentum in the planetary system, as well as its role on the control of dierent phenomena, including coronal and cromospherical emission and on the ones due of tidal effects. In spite of the continuous solid advances made on the study of the characteristics and properties of planet host stars, the main features of their rotational behavior is are not well established yet. In this context, the present work brings an unprecedented study about the
rotation and angular
momentum of planet-harbouring stars, as well as the correlation between
rotation and
stellar and planetary physical properties. Our analysis is based on a sample of 232 extrasolar planets, orbiting 196 stars of dierent luminosity classes and spectral types. In addition to the study of their rotational behavior, the behavior of the physical properties
of stars and their orbiting planets was also analyzed, including
stellar mass and metallicity, as well as the planetary orbital parameters. As main results we can underline that the
rotation of stars with planets present two clear features: stars with Tef lower than about 6000 K have slower rotations, while among stars with Tef > 6000 K we and moderate
and fast rotations, though there are a few exceptions. We also show that stars with planets follow mostly the Krafts law, namely < J > / v rot. In this same idea we show
that the
rotation versus age relation of stars with planets follows, at least qualitatively, the Skumanich and Pace & Pasquini laws. The relation
rotation versus orbital period
also points for a very interesting result, with planet-harbouring stars with shorter orbital periods present rather enhanced
rotation
Advisors/Committee Members: Medeiros, José Renan de (advisor), CPF:08896135400 (advisor), http://lattes.cnpq.br/9151590034650501 (advisor).
Subjects/Keywords: Rotação estelar;
Exoplanetas;
Momento angular;
Estrelas hospedeiras;
Parâmetros físicos;
Stellar rotation;
Exoplanets;
Angular momentum;
Stars with planets;
Physical parameter
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Nascimento, S. A. d. (2008). Propriedades físicas de planetas extrasolares
. (Masters Thesis). Universidade do Rio Grande do Norte. Retrieved from http://repositorio.ufrn.br/handle/123456789/18579
Chicago Manual of Style (16th Edition):
Nascimento, Sanzia Alves do. “Propriedades físicas de planetas extrasolares
.” 2008. Masters Thesis, Universidade do Rio Grande do Norte. Accessed March 05, 2021.
http://repositorio.ufrn.br/handle/123456789/18579.
MLA Handbook (7th Edition):
Nascimento, Sanzia Alves do. “Propriedades físicas de planetas extrasolares
.” 2008. Web. 05 Mar 2021.
Vancouver:
Nascimento SAd. Propriedades físicas de planetas extrasolares
. [Internet] [Masters thesis]. Universidade do Rio Grande do Norte; 2008. [cited 2021 Mar 05].
Available from: http://repositorio.ufrn.br/handle/123456789/18579.
Council of Science Editors:
Nascimento SAd. Propriedades físicas de planetas extrasolares
. [Masters Thesis]. Universidade do Rio Grande do Norte; 2008. Available from: http://repositorio.ufrn.br/handle/123456789/18579
University of Exeter
19.
Finley, A.
Constraining the angular momentum-loss rates of the Sun and other Sun-like stars.
Degree: PhD, 2020, University of Exeter
URL: http://hdl.handle.net/10871/121115
► Stellar rotation, convection, and magnetism are intricately linked in low-mass stars like the Sun. In their outer convective envelopes, the interplay of rotation and convection…
(more)
▼ Stellar rotation, convection, and magnetism are intricately linked in low-mass stars like the Sun. In their outer convective envelopes, the interplay of rotation and convection form a magnetic dynamo capable of sustaining both large and small scale magnetic fields. The strength of these magnetic fields are observed to grow with increasing rotation rate. The coronae of low-mass stars are heated by these magnetic fields (the exact mechanism of which remains under debate), such that the thermal pressure drives a quasi-steady outflow of plasma, referred to as a stellar wind. Due to the interaction of the large-scale magnetic field with the outflowing plasma, stellar winds are able to efficiently remove angular momentum from these stars. Therefore, the evolution of rotation for low-mass stars (on the the main sequence) is governed by their stellar winds, and by interrelation, the evolution of their magnetic activity and stellar wind output. In this thesis I attempt to better constrain the angular momentum-loss rates of the Sun and other Sun-like stars through the use of magnetohydrodynamic simulations combined with a broad range of observations. Though I do not find a concrete value for the solar case, I reduce the uncertainty in its value to within a factor of a few by locating key factors/quantities which limit our predictions, and further highlight the importance of understanding the solar angular momentum-loss rate in an astrophysical context. For the other Sun-like stars, I find the simulation results largely under-predict the angular momentum-loss rates implied by current rotation-evolution models. The reason(s) for this are uncertain, but likely involve uncertainties in both the observed magnetic field strengths and mass-loss rates of these stars, along with the under-prediction of how much of the surface magnetic field is ``opened'' by the stellar wind.
Subjects/Keywords: solar wind; stellar winds; astrophysics; magnetohydrodynamics; numerical simulation; rotation period evolution; low-mass stars; sun-like stars
Record Details
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Record Details
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« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Finley, A. (2020). Constraining the angular momentum-loss rates of the Sun and other Sun-like stars. (Doctoral Dissertation). University of Exeter. Retrieved from http://hdl.handle.net/10871/121115
Chicago Manual of Style (16th Edition):
Finley, A. “Constraining the angular momentum-loss rates of the Sun and other Sun-like stars.” 2020. Doctoral Dissertation, University of Exeter. Accessed March 05, 2021.
http://hdl.handle.net/10871/121115.
MLA Handbook (7th Edition):
Finley, A. “Constraining the angular momentum-loss rates of the Sun and other Sun-like stars.” 2020. Web. 05 Mar 2021.
Vancouver:
Finley A. Constraining the angular momentum-loss rates of the Sun and other Sun-like stars. [Internet] [Doctoral dissertation]. University of Exeter; 2020. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/10871/121115.
Council of Science Editors:
Finley A. Constraining the angular momentum-loss rates of the Sun and other Sun-like stars. [Doctoral Dissertation]. University of Exeter; 2020. Available from: http://hdl.handle.net/10871/121115
20.
Gehan, Charlotte.
Évolution de la rotation du cœur des étoiles sur la branche des géantes rouges : des mesures à grande échelle vers une caractérisation du transport de moment cinétique : Evolution of the core rotation of red giant branch stars : from large-scale measurements towards a characterisation of the angular momentum transport.
Degree: Docteur es, Astronomie et Astrophysique, 2018, Paris Sciences et Lettres
URL: http://www.theses.fr/2018PSLEO021
► L’astérosismologie consiste à sonder les intérieurs stellaires en détectant les ondes sismiques qui s’y propagent. Les géantes rouges, des étoiles évoluées peu massives dont l’hydrogène…
(more)
▼ L’astérosismologie consiste à sonder les intérieurs stellaires en détectant les ondes sismiques qui s’y propagent. Les géantes rouges, des étoiles évoluées peu massives dont l’hydrogène du cœur est épuisé, sont des pulsateurs de type solaire présentant des modes mixtes qui nous permettent d’accéder directement aux propriétés physiques de leur cœur. Les mesures sismiques disponibles indiquent qu’un ou plusieurs mécanismes physiques encore mal compris contrebalancent l’accélération de la rotation du cœur sous l’effet de sa contraction, en transportant du moment cinétique. La majeure partie de cette thèse a été consacrée au développement d’une méthode permettant une mesure aussi automatisée que possible de la rotation moyenne du cœur des étoiles de la branche des géantes rouges observées par le satellite Kepler (NASA). Les mesures obtenues pour environ 900 étoiles mettent en évidence que la rotation du cœur est à peu près constante le long de la branche des géantes rouges,avec des valeurs indépendantes de la masse des étoiles. Le deuxième volet de cette thèse est consacré à l’interprétation de ces résultats basée sur la modélisation stellaire. L’enjeu consiste à utiliser les mesures à grande échelle obtenues durant la première partie pour caractériser la quantité de moment cinétique qui doit être extraite localement de chaque région du cœur, à différents instants sur la branche des géantes rouges, pour différentes masses stellaires.
Asteroseismology consists in probing stellar interiors through the detection of seismic waves. Red giants are evolved low-mass stars that have exhausted hydrogen in their core. These stars are solar-type pulsators presenting mixed modes that allow us to have a direct access to the physical properties of their core. The available seismic measurements indicate that one or several mechanisms that remain poorly understood counterbalance the acceleration ofthe core rotation, resulting from its contraction, by transporting angularmomentum. The greatest part of this PhD thesis was devoted to the development of a method allowing a measurement as automated as possible of the mean core rotation of stars on the red giant branch that were observed by the Kepler satellite (NASA). The measurements that were derived for almost 900 stars highlight that the core rotation is almost constant along the red giant branch, with values largely independent of the stellar mass. The second part of this PhD thesis is devoted to the interpretation of these results based on stellar modelling. The challenge consists in using the large-scale measurements obtainedin the first part to characterise the quantity of angular momentum that has to be extracted from each layer of the core, at different timesteps on the red giant branch, for different stellar masses.
Advisors/Committee Members: Mosser, Benoît (thesis director), Michel, Eric (thesis director).
Subjects/Keywords: Physique stellaire; Astérosismologie; Géantes rouges; Rotation interne; Traitement de données; Modélisation; Stellar physics; Asteroseismology; Red giants; Internal rotation; Data analysis; Modelling; 520
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APA (6th Edition):
Gehan, C. (2018). Évolution de la rotation du cœur des étoiles sur la branche des géantes rouges : des mesures à grande échelle vers une caractérisation du transport de moment cinétique : Evolution of the core rotation of red giant branch stars : from large-scale measurements towards a characterisation of the angular momentum transport. (Doctoral Dissertation). Paris Sciences et Lettres. Retrieved from http://www.theses.fr/2018PSLEO021
Chicago Manual of Style (16th Edition):
Gehan, Charlotte. “Évolution de la rotation du cœur des étoiles sur la branche des géantes rouges : des mesures à grande échelle vers une caractérisation du transport de moment cinétique : Evolution of the core rotation of red giant branch stars : from large-scale measurements towards a characterisation of the angular momentum transport.” 2018. Doctoral Dissertation, Paris Sciences et Lettres. Accessed March 05, 2021.
http://www.theses.fr/2018PSLEO021.
MLA Handbook (7th Edition):
Gehan, Charlotte. “Évolution de la rotation du cœur des étoiles sur la branche des géantes rouges : des mesures à grande échelle vers une caractérisation du transport de moment cinétique : Evolution of the core rotation of red giant branch stars : from large-scale measurements towards a characterisation of the angular momentum transport.” 2018. Web. 05 Mar 2021.
Vancouver:
Gehan C. Évolution de la rotation du cœur des étoiles sur la branche des géantes rouges : des mesures à grande échelle vers une caractérisation du transport de moment cinétique : Evolution of the core rotation of red giant branch stars : from large-scale measurements towards a characterisation of the angular momentum transport. [Internet] [Doctoral dissertation]. Paris Sciences et Lettres; 2018. [cited 2021 Mar 05].
Available from: http://www.theses.fr/2018PSLEO021.
Council of Science Editors:
Gehan C. Évolution de la rotation du cœur des étoiles sur la branche des géantes rouges : des mesures à grande échelle vers une caractérisation du transport de moment cinétique : Evolution of the core rotation of red giant branch stars : from large-scale measurements towards a characterisation of the angular momentum transport. [Doctoral Dissertation]. Paris Sciences et Lettres; 2018. Available from: http://www.theses.fr/2018PSLEO021
University of Florida
21.
Hoffmann, Sara Witherow.
Variations of the H and K emission lines of singly ionized calcium in the eclipsing binary star system AR Lacertae.
Degree: 1983, University of Florida
URL: https://ufdc.ufl.edu/AA00003837
Subjects/Keywords: Eclipses; Emission spectra; Latitude; Light curves; Spectroscopy; Starspots; Stellar evolution; Stellar rotation; Stellar spectra; Wavelengths; Astronomical spectroscopy; Eclipsing binaries – Spectra
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APA (6th Edition):
Hoffmann, S. W. (1983). Variations of the H and K emission lines of singly ionized calcium in the eclipsing binary star system AR Lacertae. (Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/AA00003837
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hoffmann, Sara Witherow. “Variations of the H and K emission lines of singly ionized calcium in the eclipsing binary star system AR Lacertae.” 1983. Thesis, University of Florida. Accessed March 05, 2021.
https://ufdc.ufl.edu/AA00003837.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hoffmann, Sara Witherow. “Variations of the H and K emission lines of singly ionized calcium in the eclipsing binary star system AR Lacertae.” 1983. Web. 05 Mar 2021.
Vancouver:
Hoffmann SW. Variations of the H and K emission lines of singly ionized calcium in the eclipsing binary star system AR Lacertae. [Internet] [Thesis]. University of Florida; 1983. [cited 2021 Mar 05].
Available from: https://ufdc.ufl.edu/AA00003837.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hoffmann SW. Variations of the H and K emission lines of singly ionized calcium in the eclipsing binary star system AR Lacertae. [Thesis]. University of Florida; 1983. Available from: https://ufdc.ufl.edu/AA00003837
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
22.
McGill, Meghan A.
Gravitational Darkening of Classical Be Stars.
Degree: 2013, University of Western Ontario
URL: https://ir.lib.uwo.ca/etd/1256
► Be stars are rapidly rotating B-type stars that possess a gaseous disk formed by matter released from the rapidly rotating, central star. The disk produces…
(more)
▼ Be stars are rapidly rotating B-type stars that possess a gaseous disk formed by matter released from the rapidly rotating, central star. The disk produces the characteristic observational features of these objects: hydrogen emission lines, particularly Hα, infrared excess, and continuum polarization. Gravitational darkening is a phenomenon associated with stellar rotation. It causes a reduction of the stellar effective temperature towards the equator and a redirection of energy towards the poles. Rotation also distorts the star, increasing its equatorial radius. It is an important physical effect in these star-disk systems because the photoionizing radiation from the star is essentially the sole energy source for the disk. The effect of gravitational darkening on models of the thermal structure of Be star disks is systematically studied for a wide range of Be star spectral types, rotation rates, and disk densities. Additionally, the effects of rapid rotation on model Hα lines, spectral energy distributions (SED) and photometric colours are investigated. To achieve this, gravitational darkening has been added to the bedisk and beray codes to produce circumstellar disk models and synthetic observables that include the change in the effective temperature with latitude and the non-spherical shape of the star. The effect of gravitational darkening on disk temperature is generally significant for rotation rates above 80 % of critical rotation. The bulk of the disk material becomes cooler with rotation. For example in a dense disk surrounding a B0V central star rotating at 95 % of its critical velocity, the density-averaged disk temperature is ≈ 2500 K cooler than its non-rotating counterpart. The effect of gravity darkening on observables such as the Hα line, spectral energy distributions, and colours is found to be primarily through the change in the stellar surface brightness with rotation.
Subjects/Keywords: Radiative transfer; circumstellar matter; Be stars; stellar rotation
…vertically-averaged, density-weighted temperature with disk radius for various stellar rotation… …5.1 Change in four disk temperature diagnostics with increasing
stellar rotation and varying… …weighted temperature with disk radius for various stellar rotation rates and disk
densities for… …radially-averaged temperature profile for various stellar rotation rates and disk densities for… …stellar effective temperatures including the effects of rotation versus rotation…
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APA (6th Edition):
McGill, M. A. (2013). Gravitational Darkening of Classical Be Stars. (Thesis). University of Western Ontario. Retrieved from https://ir.lib.uwo.ca/etd/1256
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
McGill, Meghan A. “Gravitational Darkening of Classical Be Stars.” 2013. Thesis, University of Western Ontario. Accessed March 05, 2021.
https://ir.lib.uwo.ca/etd/1256.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
McGill, Meghan A. “Gravitational Darkening of Classical Be Stars.” 2013. Web. 05 Mar 2021.
Vancouver:
McGill MA. Gravitational Darkening of Classical Be Stars. [Internet] [Thesis]. University of Western Ontario; 2013. [cited 2021 Mar 05].
Available from: https://ir.lib.uwo.ca/etd/1256.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
McGill MA. Gravitational Darkening of Classical Be Stars. [Thesis]. University of Western Ontario; 2013. Available from: https://ir.lib.uwo.ca/etd/1256
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
23.
Simonian, Gregory Vahag Aghabekian.
Double Trouble: The Impact of Binarity on Large Stellar
Rotation Datasets.
Degree: PhD, Astronomy, 2019, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1563439631310165
► The Kepler satellite revolutionized our understanding of stellar rotation by providing tens of thousands of rotation periods for stars in the Kepler field, including a…
(more)
▼ The Kepler satellite revolutionized our understanding
of
stellar rotation by providing tens of thousands of
rotation
periods for stars in the Kepler field, including a substantial
fraction of rapid rotators. I explore the nature of the rapid
rotators there both using Gaia parallazes and spectra from
APOGEE.One expected source of rapid rotators in the Kepler field is
a population of tidally-synchronized binaries. I test the binary
nature of the Kepler rapid rotators using Gaia parallaxes to
distinguish photometric binaries (PBs) from single stars on the
unevolved lower main sequence, and compare their distribution of
rotation properties to those of single stars both with and without
APOGEE spectroscopic characterization. I find that 59% of stars
with 1.5 day < P < 7 day lie 0.3 mag above the main sequence,
compared with 28% of the full
rotation sample. The fraction of
stars in the same period range is 1.7 ± 0.1% of the total sample
analyzed for
rotation periods. Both the photometric binary fraction
and the fraction of rapid rotators are consistent with a population
of non-eclipsing short period binaries inferred from Kepler
eclipsing binary data after correcting for inclination. This
suggests that the rapid rotators are dominated by
tidally-synchronized binaries rather than single-stars obeying
traditional angular momentum evolution. This finding provokes
caution against interpreting rapid
rotation in the Kepler field as
a signature of youth. Following up this new sample of 217 candidate
tidally-synchronized binaries will help further understand tidal
processes in stars.I also use the 5466 spectroscopic v sin i
measurements of Kepler dwarfs and subgiants from the APOGEE survey
to explore
stellar rotation in late-type dwarfs. I find a detection
threshold of 10 km/s, which also allows me to explore the spindown
of intermediate-mass stars leaving the main sequence, merger
products, young stars, and tidally-synchronized binaries. I use
Gaia parallaxes and APOGEE temperatures to calculate radii and to
search for photometric binaries. For the unevolved lower main
sequence, I see the same concentration toward rapid
rotation in
photometric binaries as that observed in
rotation period data, but
at an enhanced rate. I attribute this difference to unresolved
spectroscopic binaries with velocity displacements on the order of
the APOGEE resolution, which can spuriously overestimate rotational
broadening. Among cool, unevolved stars where rapid single star
rotation is not expected, I find an excess detection rate of 4 ±
1%, which I argue is a measure of the impact of this phenomenon.
For the subgiants, I use asteroseismic data to demonstrate that
period and v sin i methods agree, indicating the v sin i
measurements are less impacted by the presence of binaries for
these targets. There is clear evidence for a transition between
rapid and slow
rotation on the subgiant branch in the domain
predicted by modern angular momentum evolution models, with
detections on the hot side much larger than the background from
binary stars. I also…
Advisors/Committee Members: Pinsonneault, Marc (Advisor).
Subjects/Keywords: Astronomy; stellar rotation; late-type stars; close binaries
…stellar
populations (Skumanich 1972), and correlations between rotation and age have… …studies of stellar rotation for cool stars have
focused on young, solar metallicity clusters… …to measure stellar rotation in
old field populations. Large-scale analyses have extracted… …stellar rotation.
With the release of substantial rotation data with Kepler and APOGEE with
the… …dependence of stellar rotation is that the rotation periods and metallicity
must be measured…
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APA ·
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Manager
APA (6th Edition):
Simonian, G. V. A. (2019). Double Trouble: The Impact of Binarity on Large Stellar
Rotation Datasets. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1563439631310165
Chicago Manual of Style (16th Edition):
Simonian, Gregory Vahag Aghabekian. “Double Trouble: The Impact of Binarity on Large Stellar
Rotation Datasets.” 2019. Doctoral Dissertation, The Ohio State University. Accessed March 05, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1563439631310165.
MLA Handbook (7th Edition):
Simonian, Gregory Vahag Aghabekian. “Double Trouble: The Impact of Binarity on Large Stellar
Rotation Datasets.” 2019. Web. 05 Mar 2021.
Vancouver:
Simonian GVA. Double Trouble: The Impact of Binarity on Large Stellar
Rotation Datasets. [Internet] [Doctoral dissertation]. The Ohio State University; 2019. [cited 2021 Mar 05].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1563439631310165.
Council of Science Editors:
Simonian GVA. Double Trouble: The Impact of Binarity on Large Stellar
Rotation Datasets. [Doctoral Dissertation]. The Ohio State University; 2019. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1563439631310165
Georgia State University
24.
Huang, Wenjin.
Spectral Line Synthesis for Hot stars.
Degree: PhD, Physics and Astronomy, 2005, Georgia State University
URL: https://scholarworks.gsu.edu/phy_astr_diss/2
► I developed a spectrum synthesis method to investigate the physical properties of hot OB main sequence (MS) stars, which are often rapid rotators. The code…
(more)
▼ I developed a spectrum synthesis method to investigate the physical properties of
hot OB main sequence (MS) stars, which are often rapid rotators. The code realistically simulates the surface conditions
of rapidly rotating stars, considering the rotationally-deformed
stellar shape
and gravity darkening effect. Comparing the synthesized absorption line profiles with the observed spectra of the member stars of 19 young Galactic clusters, I determined the projected rotational velocities of 496 stars.
The average surface temperature and gravity for most of these objects were then derived from Hγ line fits. The polar gravity of each star was estimated as a good
indicator of the evolutionary status of the star. The derived parameters show that massive rotators spin down during their MS phase.
The He abundance data (measured by fitting the He I lines) also favor the theoretical prediction that rotationally-induced mixing
can gradually enrich the surface helium abundance through the MS phase. A quicker
spin-down is evident in the lower mass star group where a large portion of helium peculiar stars are found. This correlation
implies that strong
stellar magnetic fields may exist on the surface of these lower mass stars.
The same method is also applied to interferometric observations from the CHARA Array of a nearby rapid rotator, Regulus. By combining results from spectroscopic and interferometric analysis, the shape, space orientation, mass, and surface temperature distribution of Regulus are firmly determined. This analysis provides the first evidence
of the gravity darkening phenomenon among stars that are not components of an eclipsing binary system. The surprisingly high luminosity determined for Regulus appears to agree with the theoretical prediction that rapid rotator can become more luminous as rotationally-induced mixing brings fresh hydrogen down to the core.
Finally I present an extension of the model that simulates the shape, velocity, and temperature variations of a star
experiencing nonradial pulsation. I
simulated and analyzed the line profile variations in the spectra of ε Per, a B0.7~III star with strong evidence of nonradial pulsation (NRP). A comparison of
the model simulations and observations indicates that the pulsations of ε Per have a corresponding local temperature
variation that is out of phase with the radial oscillation (a non-adiabatic phase lag).
Advisors/Committee Members: Douglas R. Gies - Chair, Richard H. D. Townsend, H. Richard Miller, Paul J. Wiita, Xiaochun He, William G Bagnuolo.
Subjects/Keywords: Non-Radial Pulsation; Spectral Line Profiles; Spectrum Synthesis; Stellar Rotation; Massive Stars; Stellar Abundances; Galactic Clusters; Astrophysics and Astronomy; Physics
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APA ·
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APA (6th Edition):
Huang, W. (2005). Spectral Line Synthesis for Hot stars. (Doctoral Dissertation). Georgia State University. Retrieved from https://scholarworks.gsu.edu/phy_astr_diss/2
Chicago Manual of Style (16th Edition):
Huang, Wenjin. “Spectral Line Synthesis for Hot stars.” 2005. Doctoral Dissertation, Georgia State University. Accessed March 05, 2021.
https://scholarworks.gsu.edu/phy_astr_diss/2.
MLA Handbook (7th Edition):
Huang, Wenjin. “Spectral Line Synthesis for Hot stars.” 2005. Web. 05 Mar 2021.
Vancouver:
Huang W. Spectral Line Synthesis for Hot stars. [Internet] [Doctoral dissertation]. Georgia State University; 2005. [cited 2021 Mar 05].
Available from: https://scholarworks.gsu.edu/phy_astr_diss/2.
Council of Science Editors:
Huang W. Spectral Line Synthesis for Hot stars. [Doctoral Dissertation]. Georgia State University; 2005. Available from: https://scholarworks.gsu.edu/phy_astr_diss/2
25.
Chatzopoulos, Emmanouil.
Superluminous supernovae : theory and observations.
Degree: PhD, Astronomy, 2013, University of Texas – Austin
URL: http://hdl.handle.net/2152/21758
► The discovery of superluminous supernovae in the past decade challenged our understanding of explosive stellar death. Subsequent extensive observations of superluminous supernova light curves and…
(more)
▼ The discovery of superluminous supernovae in the past decade challenged our understanding of explosive
stellar death. Subsequent extensive observations of superluminous supernova light curves and spectra has provided some insight for the nature of these events. We present observations of one of the most luminous self-interacting supernovae ever observed, the hydrogen-rich SN 2008am discovered by the Robotic Optical Transient Search Experiment Supernova Verification Project with the ROTSE-IIIb telescope located in the McDonald Observatory. We provide theoretical modeling of superluminous supernova light curves and fit the models to a number of observed events and similar transients in order to understand the mechanism that is responsible for the vast amounts of energy emitted by these explosions. The models we investigate include deposition of energy due to the radioactive decays of massive amounts of nickel-56, interaction of supernova ejecta with a dense circumstellar medium and magnetar spin-down. To probe the nature of superluminous supernovae progenitor stars we study the evolution of massive stars, including important effects such as
rotation and magnetic fields, and perform multi-dimensional hydrodynamics simulations of the resulting explosions. The effects of rotational mixing are also studied in solar-type secondary stars in cataclysmic variable binary star systems in order to provide an explanation for some carbon-depleted examples of this class. We find that most superluminous supernovae can be explained by violent interaction of the SN ejecta with >1 Msun dense circumstellar shells ejected by the progenitor stars in the decades preceding the SN explosion.
Advisors/Committee Members: Wheeler, J. Craig (advisor).
Subjects/Keywords: Supernovae; Stellar evolution; Massive stars; Circumstellar matter; Light curve; Stellar rotation; Hydrodynamics
…mass stellar models for different degrees
of ZAMS rotation. Filled black squares indicate… …Effects of Rotation on the Minimum Mass of Primordial Progenitors of Pair Instability… …xii
181
6.1
Characteristics of the stellar models discussed in this work. . .
7.1… …included in the calculations. The dotted lines mark the ZAMS mass and rotation
level grid for the… …instability
region as determined by the stellar equation of state. . . . . . 258
The internal…
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APA ·
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MLA ·
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CSE |
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APA (6th Edition):
Chatzopoulos, E. (2013). Superluminous supernovae : theory and observations. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/21758
Chicago Manual of Style (16th Edition):
Chatzopoulos, Emmanouil. “Superluminous supernovae : theory and observations.” 2013. Doctoral Dissertation, University of Texas – Austin. Accessed March 05, 2021.
http://hdl.handle.net/2152/21758.
MLA Handbook (7th Edition):
Chatzopoulos, Emmanouil. “Superluminous supernovae : theory and observations.” 2013. Web. 05 Mar 2021.
Vancouver:
Chatzopoulos E. Superluminous supernovae : theory and observations. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2013. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/2152/21758.
Council of Science Editors:
Chatzopoulos E. Superluminous supernovae : theory and observations. [Doctoral Dissertation]. University of Texas – Austin; 2013. Available from: http://hdl.handle.net/2152/21758
University of Florida
26.
Morgan, Thomas Harlow, 1945-.
Fluid dynamics of circumstellar material associated with Be stars.
Degree: 1972, University of Florida
URL: https://ufdc.ufl.edu/AA00011140
Subjects/Keywords: Approximation; Be stars; Coordinate systems; Emission spectra; Equations of motion; Mathematical variables; Stellar rotation; Stellar spectra; Time dependence; Velocity; B stars; Stars – Atmospheres; Stars – Spectra
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to Zotero / EndNote / Reference
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APA (6th Edition):
Morgan, Thomas Harlow, 1. (1972). Fluid dynamics of circumstellar material associated with Be stars. (Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/AA00011140
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Morgan, Thomas Harlow, 1945-. “Fluid dynamics of circumstellar material associated with Be stars.” 1972. Thesis, University of Florida. Accessed March 05, 2021.
https://ufdc.ufl.edu/AA00011140.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Morgan, Thomas Harlow, 1945-. “Fluid dynamics of circumstellar material associated with Be stars.” 1972. Web. 05 Mar 2021.
Vancouver:
Morgan, Thomas Harlow 1. Fluid dynamics of circumstellar material associated with Be stars. [Internet] [Thesis]. University of Florida; 1972. [cited 2021 Mar 05].
Available from: https://ufdc.ufl.edu/AA00011140.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Morgan, Thomas Harlow 1. Fluid dynamics of circumstellar material associated with Be stars. [Thesis]. University of Florida; 1972. Available from: https://ufdc.ufl.edu/AA00011140
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Florida
27.
Twigg, Laurence William, 1951- ( Dissertant ).
An Analysis of the Rossiter effect in algol-type eclipsing binary systems.
Degree: 1979, University of Florida
URL: https://ufdc.ufl.edu/UF00099116
One of the fundamental parameters of a star is its rate of axial
Subjects/Keywords: Eclipses; Eclipsing binary stars; Emission spectra; Hertzsprung Russell diagrams; Light curves; Radial velocity; Spectroscopy; Stellar classification; Stellar rotation; Velocity; Astronomy thesis Ph. D; Eclipsing binaries; Stars – Rotation; Miami metropolitan area ( local )
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APA ·
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Twigg, Laurence William, 1. (. D. ). (1979). An Analysis of the Rossiter effect in algol-type eclipsing binary systems. (Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UF00099116
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Twigg, Laurence William, 1951- ( Dissertant ). “An Analysis of the Rossiter effect in algol-type eclipsing binary systems.” 1979. Thesis, University of Florida. Accessed March 05, 2021.
https://ufdc.ufl.edu/UF00099116.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Twigg, Laurence William, 1951- ( Dissertant ). “An Analysis of the Rossiter effect in algol-type eclipsing binary systems.” 1979. Web. 05 Mar 2021.
Vancouver:
Twigg, Laurence William 1(D). An Analysis of the Rossiter effect in algol-type eclipsing binary systems. [Internet] [Thesis]. University of Florida; 1979. [cited 2021 Mar 05].
Available from: https://ufdc.ufl.edu/UF00099116.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Twigg, Laurence William 1(D). An Analysis of the Rossiter effect in algol-type eclipsing binary systems. [Thesis]. University of Florida; 1979. Available from: https://ufdc.ufl.edu/UF00099116
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Florida
28.
Fleck, Robert Charles, 1949-.
Magnetic braking during star formation.
Degree: 1977, University of Florida
URL: https://ufdc.ufl.edu/UF00097484
Subjects/Keywords: Angular momentum; Braking; Cooling; Cosmic rays; Ionization; Magnetic fields; Magnetism; Magnets; Main sequence stars; Stellar rotation; Astronomy thesis Ph. D; Stars – Evolution; Stars – Rotation; Stars, New
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APA (6th Edition):
Fleck, Robert Charles, 1. (1977). Magnetic braking during star formation. (Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UF00097484
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Fleck, Robert Charles, 1949-. “Magnetic braking during star formation.” 1977. Thesis, University of Florida. Accessed March 05, 2021.
https://ufdc.ufl.edu/UF00097484.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Fleck, Robert Charles, 1949-. “Magnetic braking during star formation.” 1977. Web. 05 Mar 2021.
Vancouver:
Fleck, Robert Charles 1. Magnetic braking during star formation. [Internet] [Thesis]. University of Florida; 1977. [cited 2021 Mar 05].
Available from: https://ufdc.ufl.edu/UF00097484.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Fleck, Robert Charles 1. Magnetic braking during star formation. [Thesis]. University of Florida; 1977. Available from: https://ufdc.ufl.edu/UF00097484
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Florida
29.
Davies, Chad Leslie, 1966-.
Numerical modeling of large N galactic disk systems.
Degree: PhD, Physics, 1995, University of Florida
URL: https://ufdc.ufl.edu/AA00058066
Subjects/Keywords: Angular momentum; Density; Galaxies; Galaxy rotation curves; Mass; Particle mass; Simulations; Star formation; Stellar disks; Velocity; Disks (Astrophysics)
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Davies, Chad Leslie, 1. (1995). Numerical modeling of large N galactic disk systems. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/AA00058066
Chicago Manual of Style (16th Edition):
Davies, Chad Leslie, 1966-. “Numerical modeling of large N galactic disk systems.” 1995. Doctoral Dissertation, University of Florida. Accessed March 05, 2021.
https://ufdc.ufl.edu/AA00058066.
MLA Handbook (7th Edition):
Davies, Chad Leslie, 1966-. “Numerical modeling of large N galactic disk systems.” 1995. Web. 05 Mar 2021.
Vancouver:
Davies, Chad Leslie 1. Numerical modeling of large N galactic disk systems. [Internet] [Doctoral dissertation]. University of Florida; 1995. [cited 2021 Mar 05].
Available from: https://ufdc.ufl.edu/AA00058066.
Council of Science Editors:
Davies, Chad Leslie 1. Numerical modeling of large N galactic disk systems. [Doctoral Dissertation]. University of Florida; 1995. Available from: https://ufdc.ufl.edu/AA00058066
. 
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