subject:(shape coexistence)

University of Guelph

1. Burbadge, Christina. Investigation of excited 0+ states populated in the 162Er(p,t) reaction.

Degree: MS, Department of Physics, 2017, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/10467

► Interpreting the nature of excited states in well-deformed nuclei has been an ongoing challenge in our understanding of nuclear structure. Some of the approaches that… (more)

▼ Interpreting the nature of excited states in well-deformed nuclei has been an ongoing challenge in our understanding of nuclear structure. Some of the approaches that have been implemented to interpret the occurrence of low-lying excited 02+ states include vibrational excitations in β-phonons and γ-phonons, as well as pairing excitations. A further complication is the presence of shape coexistence which can increase the number of low-lying states, and if the shapes undergo mixing, the spectroscopic signatures can become ambiguous. An example of such a case is in the rare-earth region, where there is a rapid change in the ground state shape from N = 88 to N = 92. One of the difficulties in resolving the nature of these states is that there is a paucity of data, particularly for excited 0+ states, in the rare earth region. Two-neutron transfer reactions are ideal for probing 0+ → 0+ transitions in deformed nuclei. One of the intriguing features of the rare-earth region are the strongly-populated 0+ states that emerge in both (p, t) and (t, p) two-neutron transfer reactions that have been interpreted as signatures of shape coexistence and pairing isomerism. In the present work, excited 0+ states have been studied via the 162Er(p, t)160Er reaction at the Maier-Leibnitz Laboratory in Garching, Germany using 22 MeV and 24 MeV proton beams and the reaction products were momentum-analyzed with the Q3D magnetic spectrograph. In this work, sixty-nine levels were observed and angular momenta were assigned for thirty-eight of these states. In total, seven excited 0+ states were assigned, six of which were unknown until the present work and one of which was not definite. The cross sections of these low-lying excited 0+ states, with the 02+ state population around 18% of the ground state strength, suggests a special character for this state which is inconsistent with a β-vibration interpretation. The similarity of the population of the 02+ state in 160Er with low-lying 0+ states in N = 90 isotones suggests that the nature of these excitations are quite similar, with the possibility that the 02+ state is an example of shape coexistence. Results of the relative population of the excited 0+ states in 160Er will be presented, and placed into context with similar experiments in the N = 90 region. Advisors/Committee Members: Garrett, Paul (advisor).

Subjects/Keywords: Shape coexistence; Transfer Reactions

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APA (6^th Edition):

Burbadge, C. (2017). Investigation of excited 0+ states populated in the 162Er(p,t) reaction. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/10467

Chicago Manual of Style (16^th Edition):

Burbadge, Christina. “Investigation of excited 0+ states populated in the 162Er(p,t) reaction.” 2017. Masters Thesis, University of Guelph. Accessed April 15, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/10467.

MLA Handbook (7^th Edition):

Burbadge, Christina. “Investigation of excited 0+ states populated in the 162Er(p,t) reaction.” 2017. Web. 15 Apr 2021.

Vancouver:

Burbadge C. Investigation of excited 0+ states populated in the 162Er(p,t) reaction. [Internet] [Masters thesis]. University of Guelph; 2017. [cited 2021 Apr 15]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/10467.

Council of Science Editors:

Burbadge C. Investigation of excited 0+ states populated in the 162Er(p,t) reaction. [Masters Thesis]. University of Guelph; 2017. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/10467

University of Guelph

2. McGee, Erin. Searching for Shape Coexistence in \(^{123}Te\)(n,γ) Thermal Neutron Capture.

Degree: MS, Department of Physics, 2019, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17409

► Shape coexistence has been established in several nuclei in the ({Z}) = 50 region of the chart of nuclides, but tellurium has thus far not… (more)

Subjects/Keywords: nuclear physics; shape coexistence; tellurium; 124Te; gamma-ray spectroscopy; neutron capture

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APA (6^th Edition):

McGee, E. (2019). Searching for Shape Coexistence in \(^{123}Te\)(n,γ) Thermal Neutron Capture. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17409

Chicago Manual of Style (16^th Edition):

McGee, Erin. “Searching for Shape Coexistence in \(^{123}Te\)(n,γ) Thermal Neutron Capture.” 2019. Masters Thesis, University of Guelph. Accessed April 15, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17409.

MLA Handbook (7^th Edition):

McGee, Erin. “Searching for Shape Coexistence in \(^{123}Te\)(n,γ) Thermal Neutron Capture.” 2019. Web. 15 Apr 2021.

Vancouver:

McGee E. Searching for Shape Coexistence in \(^{123}Te\)(n,γ) Thermal Neutron Capture. [Internet] [Masters thesis]. University of Guelph; 2019. [cited 2021 Apr 15]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17409.

Council of Science Editors:

McGee E. Searching for Shape Coexistence in \(^{123}Te\)(n,γ) Thermal Neutron Capture. [Masters Thesis]. University of Guelph; 2019. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17409

3. Gratchev, Ivan. Étude expérimentale et théorique de la structure nucléaire des isotopes de sélénium riches en neutrons. : Experimental and theoretical study of the nuclear structure of the neutron-rich selenium isotopes.

Degree: Docteur es, Matériaux, Mécanique, Génie civil, Electrochimie, 2017, Université Grenoble Alpes (ComUE)

URL: http://www.theses.fr/2017GREAI078

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Le présent manuscrit de thèse regroupe les études par spectroscopie γ des noyaux 84−88Se produits par une réaction de ﬁssion induite par neutrons thermiques, sur… (more)

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Le présent manuscrit de thèse regroupe les études par spectroscopie γ des noyaux 84−88Se produits par une réaction de ﬁssion induite par neutrons thermiques, sur une cible de 235U. Cette expérience a été réalisée à l’Institut Laue-Langevin à Grenoble après du multi-détecteurs EXILL. Les données brutes recueillies par EXILL ont été traitées et analysées aﬁn de déterminer la structure des noyaux étudiés. Grâce à cette étude spectroscopique détaillée, un premier schéma de niveaux a été établi pour la première fois au 88Se et de nouveaux états excités ont été assignées à d’autre isotopes de sélénium (84-87Se). De plus, l’analyse de la corrélations angulaires a été faite pour conﬁrmer l’assignation de spins des premières états excités. Des calculs théoriques utilisant le modèle en couches (SM), le modèle collectif algébrique (ACM) et le modèle quasiparticule plus phonon (QPM), ont été eﬀectués pour interpréter la structure nucléaire et la forme du noyau d’intérêt 88Se. Selon ces modèles, le noyau 88Se est γ-instable et peut être interprété comme un noyau transitoire et sa structure nucléaire du 88Se a été bien reproduite par le modèle en couches et le modèle ACM. Les calculs du modèle QPM indiquent que le degré de collectivité de l’état 22+ du 88Se est faible parce que une composante neutronique reste dominante dans la structure de la bande γ.

The present thesis manuscript includes the nuclear spectroscopy studies of 84−88Se. A more favourable fission reaction for their study is 235U(nth, f). The measurement was performed at the PF1B cold-neutron beam facility of the Institut Laue-Langevin (ILL), Grenoble. The fission reaction has been used in conjunction with the EXILL Ge array to study excited states in the neutron-rich Se nuclei. Thanks to this spectroscopic study, a first level scheme of 88Se was established and new excited states were assigned to other selenium isotopes. Furthermore, the angular correlation studies were carried out to confirm the spin assignment of the first excited states in the 84-88Se nuclei. The theoretical calculations using the shell model (SM), the algebraic collective model (ACM) and the quasiparticle plus phonon model (QPM) were performed in order to interpret the nuclear structure and the shape of the nucleus of interest 88Se. According to these models, the nucleus 88Se is γ-unstable and can be interpreted as a transitional nucleus. The shell-model calculations using a 78Ni core and the ACM calculations reproduce the decay scheme of 88Se well. The QPM calculations show that the collectivity of second state 2+2 of 88Se is weak and that this state contains a strong quasiparticle component.

Advisors/Committee Members: Thiamova, Gabriela (thesis director), Simpson, Gary (thesis director).

Subjects/Keywords: L'effet de collectivité; Triaxialité; Coexistence de formes; Exill; Spectroscopie nucléaire; 88Se; Shape coexistence; Triaxiality; Exill; Collectivity; Nuclear spectroscopy; 88Se; 530

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APA (6^th Edition):

Gratchev, I. (2017). Étude expérimentale et théorique de la structure nucléaire des isotopes de sélénium riches en neutrons. : Experimental and theoretical study of the nuclear structure of the neutron-rich selenium isotopes. (Doctoral Dissertation). Université Grenoble Alpes (ComUE). Retrieved from http://www.theses.fr/2017GREAI078

Chicago Manual of Style (16^th Edition):

Gratchev, Ivan. “Étude expérimentale et théorique de la structure nucléaire des isotopes de sélénium riches en neutrons. : Experimental and theoretical study of the nuclear structure of the neutron-rich selenium isotopes.” 2017. Doctoral Dissertation, Université Grenoble Alpes (ComUE). Accessed April 15, 2021. http://www.theses.fr/2017GREAI078.

MLA Handbook (7^th Edition):

Gratchev, Ivan. “Étude expérimentale et théorique de la structure nucléaire des isotopes de sélénium riches en neutrons. : Experimental and theoretical study of the nuclear structure of the neutron-rich selenium isotopes.” 2017. Web. 15 Apr 2021.

Vancouver:

Gratchev I. Étude expérimentale et théorique de la structure nucléaire des isotopes de sélénium riches en neutrons. : Experimental and theoretical study of the nuclear structure of the neutron-rich selenium isotopes. [Internet] [Doctoral dissertation]. Université Grenoble Alpes (ComUE); 2017. [cited 2021 Apr 15]. Available from: http://www.theses.fr/2017GREAI078.

Council of Science Editors:

Gratchev I. Étude expérimentale et théorique de la structure nucléaire des isotopes de sélénium riches en neutrons. : Experimental and theoretical study of the nuclear structure of the neutron-rich selenium isotopes. [Doctoral Dissertation]. Université Grenoble Alpes (ComUE); 2017. Available from: http://www.theses.fr/2017GREAI078

4. Crider, Benjamin P. Nuclear Structure Relevant to Double-beta Decay: Studies of ⁷⁶Ge and ⁷⁶Se using Inelastic Neutron Scattering.

Degree: 2014, University of Kentucky

URL: https://uknowledge.uky.edu/physastron_etds/17

► While neutrino oscillations indicate that neutrino flavors mix and that neutrinos have mass, they do not supply information on the absolute mass scale of the… (more)

▼ While neutrino oscillations indicate that neutrino flavors mix and that neutrinos have mass, they do not supply information on the absolute mass scale of the three flavors of neutrinos. Currently, the only viable way to determine this mass scale is through the observation of the theoretically predicted process of neutrinoless double-beta decay (0νββ). This yet-to-be-observed decay process is speculated to occur in a handful of nuclei and has predicted half-lives greater than 10²⁵ years. Observation of 0νββ is the goal of several large-scale, multinational efforts and consists of detecting a sharp peak in the summed β energies at the Q-value of the reaction. An exceptional candidate for the observation of 0νββ is ⁷⁶Ge, which offers an excellent combination of capabilities and sensitivities, and two such collaborations, MAJORANA and GERDA, propose tonne-scale experiments that have already begun initial phases using a fraction of the material. The absolute scale of the neutrino masses hinges on a matrix element, which depends on the ground-state wave functions for both the parent (⁷⁶Ge) and daughter (⁷⁶Se) nuclei in the 0νββ decay and can only be calculated from nuclear structure models. Efforts to provide information on the applicability of these models have been undertaken at the University of Kentucky Accelerator Laboratory using gamma-ray spectroscopy following inelastic scattering reactions with monoenergetic, accelerator-produced fast neutrons. Information on new energy levels and transitions, spin and parity assignments, lifetimes, multipole mixing ratios, and transition probabilities have been determined for ⁷⁶Se, the daughter of ⁷⁶Ge 0νββ, up to 3.0 MeV. Additionally, inaccuracies in the accepted level schemes have been addressed. Observation of 0νββ requires precise knowledge of potential contributors to background within the region of interest, i.e., approximately 2039 keV for ⁷⁶Ge. In addition to backgrounds resulting from surrounding materials in the experimental setup, ⁷⁶Ge has a previously observed 3952-keV level with a de-exciting 2040-keV γ ray. This γ ray constitutes a potential background for 0νββ searches, if this level is excited. The cross sections for this level and, subsequently, for the 2040-keV γ ray has been determined in the range from 4 to 5 MeV.

Subjects/Keywords: nuclear structure; inelastic neutron scattering; neutrinoless double-beta decay; shape coexistence; Nuclear

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

APA (6^th Edition):

Crider, B. P. (2014). Nuclear Structure Relevant to Double-beta Decay: Studies of ⁷⁶Ge and ⁷⁶Se using Inelastic Neutron Scattering. (Doctoral Dissertation). University of Kentucky. Retrieved from https://uknowledge.uky.edu/physastron_etds/17

Chicago Manual of Style (16^th Edition):

Crider, Benjamin P. “Nuclear Structure Relevant to Double-beta Decay: Studies of ⁷⁶Ge and ⁷⁶Se using Inelastic Neutron Scattering.” 2014. Doctoral Dissertation, University of Kentucky. Accessed April 15, 2021. https://uknowledge.uky.edu/physastron_etds/17.

MLA Handbook (7^th Edition):

Crider, Benjamin P. “Nuclear Structure Relevant to Double-beta Decay: Studies of ⁷⁶Ge and ⁷⁶Se using Inelastic Neutron Scattering.” 2014. Web. 15 Apr 2021.

Vancouver:

Crider BP. Nuclear Structure Relevant to Double-beta Decay: Studies of ⁷⁶Ge and ⁷⁶Se using Inelastic Neutron Scattering. [Internet] [Doctoral dissertation]. University of Kentucky; 2014. [cited 2021 Apr 15]. Available from: https://uknowledge.uky.edu/physastron_etds/17.

Council of Science Editors:

Crider BP. Nuclear Structure Relevant to Double-beta Decay: Studies of ⁷⁶Ge and ⁷⁶Se using Inelastic Neutron Scattering. [Doctoral Dissertation]. University of Kentucky; 2014. Available from: https://uknowledge.uky.edu/physastron_etds/17

University of Manchester

5. Pakalidou, Nikoletta. Self-assembly of two-dimensional convex and nonconvex colloidal platelets.

Degree: 2017, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309897

► One of the most promising routes to create advanced materials is self-assembly. Self-assembly refers to the self-organisation of building blocks to form ordered structures. As… (more)

▼ One of the most promising routes to create advanced materials is self-assembly. Self-assembly refers to the self-organisation of building blocks to form ordered structures. As the properties of the self-assembled materials will inherit the properties of the basic building blocks, it is then possible to engineer the properties of the materials by tailoring the properties of the building blocks. In order to create mesoscale materials, the self-assembly of molecular building blocks of different sizes and interactions is important. Mesoscopic materials can be obtained by using larger building blocks such as nano and colloidal particles. Colloidal particles are particularly attractive as building blocks because it is possible to design interparticle interactions by controlling both the chemistry of the particlesÃƒÂ¢Ã‚Â€Ã‚Â™ surface and the properties of the solvent in which the particles are immersed. The self-assembly of spherical colloidal particles has been widely reported in the literature. However, advances in experimental techniques to produce particles with different shapes and sizes have opened new opportunities to create more complex structures that cannot be formed using spherical particles. Indeed, the particlesÃƒÂ¢Ã‚Â€Ã‚Â™ shape and effective interactions between them dictate the spatial arrangement and micro-structure of the system, which can be engineered to produce functional materials for a wide range of applications. The driving forces determining the self-assembly of colloidal particles can be modified by the use of external influences such as geometrical confinement and electromagnetic forces. Geometrical confinement, for example, has been used to design quasi two-dimensional materials such as multi-layered structures of spheres, dimers, rods, spherical caps, and monolayers of platelets with various geometries and symmetries. In this dissertation, we present three computer simulations studies using Monte Carlo and Molecular Dynamics simulations determining the self-assembly of monolayer colloidal platelets with different shapes confined in two dimensions. These particles have been selected due to recent experiments in colloidal particles with similar shapes. All the particlesÃƒÂ¢Ã‚Â€Ã‚Â™ models are represented by planar polygons, and three different effects affect- ing their self-assembly have been analysed: (a) the curvature of the particlesÃƒÂ¢Ã‚Â€Ã‚Â™ vertices; (b) the curvature of the particlesÃƒÂ¢Ã‚Â€Ã‚Â™ edges; and finally (c) the addition of functional groups on the particlesÃƒÂ¢Ã‚Â€Ã‚Â™ surface. These studies aim to demonstrate that the subtle changes on the particleÃƒÂ¢Ã‚Â€Ã‚Â™s shape can be used to engineer complex patterns for the fabrication of advanced materials. Monte Carlo simulations are performed to study the self-assembly of colloidal platelets with rounded corners with 4, 5, and 6-fold symmetries. Square platelets provide a rich phase behaviour that ranges between disorder-order and order-order phase transitions. Suprisingly, the disk-like shape of pentagons and hexagons prevents the… Advisors/Committee Members: SIPERSTEIN, FLOR F, Avendano Jimenez, Carlos, Siperstein, Flor.

Subjects/Keywords: Self-assembly; Monte Carlo simulations; Molecular Dynamics simulations; Chiral symmetry breaking; Direct coexistence method; Phase transition; Shape-persistent macrocycles

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

APA (6^th Edition):

Pakalidou, N. (2017). Self-assembly of two-dimensional convex and nonconvex colloidal platelets. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309897

Chicago Manual of Style (16^th Edition):

Pakalidou, Nikoletta. “Self-assembly of two-dimensional convex and nonconvex colloidal platelets.” 2017. Doctoral Dissertation, University of Manchester. Accessed April 15, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309897.

MLA Handbook (7^th Edition):

Pakalidou, Nikoletta. “Self-assembly of two-dimensional convex and nonconvex colloidal platelets.” 2017. Web. 15 Apr 2021.

Vancouver:

Pakalidou N. Self-assembly of two-dimensional convex and nonconvex colloidal platelets. [Internet] [Doctoral dissertation]. University of Manchester; 2017. [cited 2021 Apr 15]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309897.

Council of Science Editors:

Pakalidou N. Self-assembly of two-dimensional convex and nonconvex colloidal platelets. [Doctoral Dissertation]. University of Manchester; 2017. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309897

University of Manchester

6. Pakalidou, Nikoletta. Self-assembly of two-dimensional convex and nonconvex colloidal platelets.

Degree: PhD, 2017, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/selfassembly-of-twodimensional-convex-and-nonconvex-colloidal-platelets(072e9fad-3e34-4803-b3df-6aed3ce756c7).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.756812

► One of the most promising routes to create advanced materials is self-assembly. Self-assembly refers to the self-organisation of building blocks to form ordered structures. As… (more)

▼ One of the most promising routes to create advanced materials is self-assembly. Self-assembly refers to the self-organisation of building blocks to form ordered structures. As the properties of the self-assembled materials will inherit the properties of the basic building blocks, it is then possible to engineer the properties of the materials by tailoring the properties of the building blocks. In order to create mesoscale materials, the self-assembly of molecular building blocks of different sizes and interactions is important. Mesoscopic materials can be obtained by using larger building blocks such as nano and colloidal particles. Colloidal particles are particularly attractive as building blocks because it is possible to design interparticle interactions by controlling both the chemistry of the particles' surface and the properties of the solvent in which the particles are immersed. The self-assembly of spherical colloidal particles has been widely reported in the literature. However, advances in experimental techniques to produce particles with different shapes and sizes have opened new opportunities to create more complex structures that cannot be formed using spherical particles. Indeed, the particles' shape and effective interactions between them dictate the spatial arrangement and micro-structure of the system, which can be engineered to produce functional materials for a wide range of applications. The driving forces determining the self-assembly of colloidal particles can be modified by the use of external influences such as geometrical confinement and electromagnetic forces. Geometrical confinement, for example, has been used to design quasi two-dimensional materials such as multi-layered structures of spheres, dimers, rods, spherical caps, and monolayers of platelets with various geometries and symmetries. In this dissertation, we present three computer simulations studies using Monte Carlo and Molecular Dynamics simulations determining the self-assembly of monolayer colloidal platelets with different shapes confined in two dimensions. These particles have been selected due to recent experiments in colloidal particles with similar shapes. All the particles' models are represented by planar polygons, and three different effects affecting their self-assembly have been analysed: (a) the curvature of the particles' vertices; (b) the curvature of the particles' edges; and finally (c) the addition of functional groups on the particles' surface. These studies aim to demonstrate that the subtle changes on the particle's shape can be used to engineer complex patterns for the fabrication of advanced materials. Monte Carlo simulations are performed to study the self-assembly of colloidal platelets with rounded corners with 4, 5, and 6-fold symmetries. Square platelets provide a rich phase behaviour that ranges between disorder-order and order-order phase transitions. Suprisingly, the disk-like shape of pentagons and hexagons prevents the total crystallisation of these systems, even at a high pressure state. A…

Subjects/Keywords: 660; Shape-persistent macrocycles; Phase transition; Chiral symmetry breaking; Direct coexistence method; Monte Carlo simulations; Self-assembly; Molecular Dynamics simulations

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

APA (6^th Edition):

Pakalidou, N. (2017). Self-assembly of two-dimensional convex and nonconvex colloidal platelets. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/selfassembly-of-twodimensional-convex-and-nonconvex-colloidal-platelets(072e9fad-3e34-4803-b3df-6aed3ce756c7).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.756812

Chicago Manual of Style (16^th Edition):

Pakalidou, Nikoletta. “Self-assembly of two-dimensional convex and nonconvex colloidal platelets.” 2017. Doctoral Dissertation, University of Manchester. Accessed April 15, 2021. https://www.research.manchester.ac.uk/portal/en/theses/selfassembly-of-twodimensional-convex-and-nonconvex-colloidal-platelets(072e9fad-3e34-4803-b3df-6aed3ce756c7).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.756812.

MLA Handbook (7^th Edition):

Pakalidou, Nikoletta. “Self-assembly of two-dimensional convex and nonconvex colloidal platelets.” 2017. Web. 15 Apr 2021.

Vancouver:

Pakalidou N. Self-assembly of two-dimensional convex and nonconvex colloidal platelets. [Internet] [Doctoral dissertation]. University of Manchester; 2017. [cited 2021 Apr 15]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/selfassembly-of-twodimensional-convex-and-nonconvex-colloidal-platelets(072e9fad-3e34-4803-b3df-6aed3ce756c7).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.756812.

Council of Science Editors:

Pakalidou N. Self-assembly of two-dimensional convex and nonconvex colloidal platelets. [Doctoral Dissertation]. University of Manchester; 2017. Available from: https://www.research.manchester.ac.uk/portal/en/theses/selfassembly-of-twodimensional-convex-and-nonconvex-colloidal-platelets(072e9fad-3e34-4803-b3df-6aed3ce756c7).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.756812

7. Mancuso, Clément. Recherche de déformation dans des noyaux riches en neutrons : Search for deformation in neutron rich nuclei.

Degree: Docteur es, Physique nucléaire, 2016, Lyon

URL: http://www.theses.fr/2016LYSE1095

►

Actuellement, le noyau de l'atome sert dans diverses utilisations courantes. Pourtant, notre compréhension que de cet objet n'est pas complète. C'est pourquoi la recherche nucléaire… (more)

▼

Actuellement, le noyau de l'atome sert dans diverses utilisations courantes. Pourtant, notre compréhension que de cet objet n'est pas complète. C'est pourquoi la recherche nucléaire est nécessaire. Parmi cet ensemble vaste, ce manuscrit s'intéresse à l'étude des changements de forme dans les isotopes riches en neutrons des séries Ru et Sr. Le sujet est d'abord cerné dans un chapitre de concepts théoriques de la physique nucléaire. Un second chapitre décrit l'expérience permettant de produire les isotopes d'intérêt. Cette expérience de spectroscopie gamma est réalisée avec un multidétecteur HPGe composé à partir d'EXOGAM et complété de cristaux GASP et LOHENGRIN. Cette expérience consiste en la fission du 241Pu induite par neutrons froids fournis par le réacteur de l'Institut Laue Langevin. Elle fait partie de la campagne EXILL. Le deuxième chapitre traite également de la pré-analyse des données. Après avoir montré les effets d'une pré-sélection des événements en multiplicité, les résultats obtenus concernant les isotopes 108Ru à 115Ru, et 92Sr à 96Sr sont abordés dans le troisième chapitre. Enfin, le quatrième chapitre replace ces résultats dans des ensembles plus larges des parties riches en neutrons des deux séries. Ces séries sont également replacées dans le contexte de leur région de masse.La région d'intérêt est riche en changement de forme, avec l'enrichissement neutronique ou avec l'excitation des noyaux. Ces changements sont plutôt bien décrits par certains modèles, mais ces derniers peinent encore à en décrire les limites. Leurs déterminations précises est essentielle pour contraindre les modèles

Nowadays, the atomic nucleus is used in a variety of common way. Nevertheless, this object is not fully understood yet. This is why nuclear physics research is still needed. Among the large number of nuclear physics topics, this work is interested in the study of shape changes in neutron rich Ru and Sr isotopes. The subject is figured out in the first chapter, dealing with theoretical concepts about nuclear physics. A second chapter describes the experiment permitting to produce the isotopes of interest. This gamma-ray spectroscopy experiment has been realized with a HPGe multidetector made from EXOGAM and completed by GASP and LOHENGRIN detectors. This experiment consists of the cold neutron, supplied by the reactor of the Institute Laue Langevin, induced fission of 241Pu. This experiment is a part of the EXILL measurement campaign. The second chapter also deals with the data pre-analysis of this experiment. After showing the effects of a multiplicity cut on event preselection, the obtained results concerning 108Ru to 115Ru and 92Sr to 96Sr isotopes are presented on the third chapter. Finally, the fourth chapter puts these results in a wider part of the neutron rich side of both series. These last ones are also placed in their mass region context.The region of interest is rich in shape change, whether with neutronic enrichment or with excitation energy. These changes are rather well described by certain models,…

Advisors/Committee Members: Guinet, Daniel (thesis director).

Subjects/Keywords: Spectroscopie gamma; Structure nucléaire; Triaxialité; Coexistence de formes; EXOGAM; Isotopes de Ru et Sr riches en neutrons; Analyse de données; Déformation nucléaire; Gamma-ray spectroscopy; Nuclear structure; Triaxiality; Shape coexistence; EXOGAM; Neutron rich Ru and Sr isotopes; Data analysis; Nuclear deformation; 539.7

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

APA (6^th Edition):

Mancuso, C. (2016). Recherche de déformation dans des noyaux riches en neutrons : Search for deformation in neutron rich nuclei. (Doctoral Dissertation). Lyon. Retrieved from http://www.theses.fr/2016LYSE1095

Chicago Manual of Style (16^th Edition):

Mancuso, Clément. “Recherche de déformation dans des noyaux riches en neutrons : Search for deformation in neutron rich nuclei.” 2016. Doctoral Dissertation, Lyon. Accessed April 15, 2021. http://www.theses.fr/2016LYSE1095.

MLA Handbook (7^th Edition):

Mancuso, Clément. “Recherche de déformation dans des noyaux riches en neutrons : Search for deformation in neutron rich nuclei.” 2016. Web. 15 Apr 2021.

Vancouver:

Mancuso C. Recherche de déformation dans des noyaux riches en neutrons : Search for deformation in neutron rich nuclei. [Internet] [Doctoral dissertation]. Lyon; 2016. [cited 2021 Apr 15]. Available from: http://www.theses.fr/2016LYSE1095.

Council of Science Editors:

Mancuso C. Recherche de déformation dans des noyaux riches en neutrons : Search for deformation in neutron rich nuclei. [Doctoral Dissertation]. Lyon; 2016. Available from: http://www.theses.fr/2016LYSE1095

Université Paris-Sud – Paris XI

8. Zerrouki, Thileli. Triaxialité et coexistence de forme dans les noyaux proches de la fermeture de couche N = 82 : évolution de forme et rotation magnétique dans ¹⁴¹Nd : Triaxiality and shape coexistence in nuclei near N=82 shell closure : shape evolution and magnetic rotation in ¹⁴¹Nd.

Degree: Docteur es, Physique, 2015, Université Paris-Sud – Paris XI

URL: http://www.theses.fr/2015PA112069

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Ce travail de thèse a été consacré à l'étude des noyaux avec quelques trous dans la fermeture de couche N = 82, qui présente une… (more)

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Ce travail de thèse a été consacré à l'étude des noyaux avec quelques trous dans la fermeture de couche N = 82, qui présente une très riche variété d'excitations à hauts spins. La particularité de ces noyaux est la présence de coexistence de forme (sphérique et/ou triaxiale) à des spins très élevés. Durant ma thèse, j’ai analysé une expérience effectuée avec le multidétecteur Euroball à l’IPHC (Strasbourg) pour l'étude des états de haut spin dans le noyau ¹⁴¹Nd, peuplé en utilisant la réaction de fusion-évaporation : ⁹⁶Zr (⁴⁸Ca, 3n). Nous avons identifié plusieurs bandes à spin élevé et développé le schéma de niveaux jusqu'à une énergie d'excitation et spin de l’ordre de 19 MeV et 81/2⁻ respectivement, qui sont bien plus élevés par rapport à celui publié précédemment (9.4 MeV et 49/2h). Trois nouvelles bandes dipôlaires et trois nouvelles bandes rotationnelles quadrupolaires ont été identifiées. La séquence principale yrast a aussi été étendue jusqu’au spin 61/2⁻.Nous avons réalisé des calculs théoriques détaillés des bandes observées, en intégrant, pour la première fois, les résultats qu’on a obtenus par les modèles Cranked Nilsson-Strutinsky (CNS) et Tilted Axis Cranking (TAC). Une interprétation cohérente de la plupart des bandes observées a été réalisée, qui semblent être basées sur des minimas d’énergies presque sphérique pour les séquences principales, légèrement déformée pour les bandes dipoalires et triaxiale déformée pour les bandes quadrupolaires. La structure de niveau observée dans le noyau ¹⁴¹Nd révèle la capacité des noyaux avec quelques trous dans la fermeture de couche N = 82 à acquérir des formes différentes de tourner autour d'un axe principal ou d'un axe incliné par rapport au système de référence intrinsèque, comme dans le cas des noyaux ¹³⁸Nd et ¹⁴⁰Nd récemment étudiés par notre groupe. Tous ces résultats représentent donc un fort soutien à l'existence de la forme nucléaire triaxiale stable à hauts spins dans cette région de masse.

This PhD work was devoted to the study of exotic nuclear rotation and stable triaxiality at very high spin. In, nuclei with a few holes in the N = 82 shell closure, which exhibit a large variety of excitations at medium and high spins. The peculiar feature of these nuclei is the existence of coexisting shapes, spherical and triaxial, up to very high spins.During my PhD I analyzed an experiment performed with the Euroball multidetector at IPHC (Strasbourg) for the study of high-spin states in ¹⁴¹Nd populated using the ⁹⁶Zr (⁴⁸Ca, 3n) fusion-evaporation reaction. We have identified several high-spin bands and developed the level scheme up to an excitation energy and spin of 19 MeV and 81/2⁻ , respectively, which are much higher than previously published (9.4 MeV and 49⁄2 ℏ). Three new dipole bands and three new ΔI = 2 rotational bands have been identified. The main yrast sequence was extended up to spin 61/2⁻.A detailed interpretation of the observed bands was performed, for the first time, using theoretical calculations with Cranked Nilsson-Strutinsky (CNS) and the…

Advisors/Committee Members: Petrache, Costel (thesis director).

Subjects/Keywords: Structure nucléaire; Spectroscopie nucléaire; Corrélations angulaires (physique nucléaire); Coïncidences; Rapport DCO; Réactions nucléaires; Coexistence de forme; Hauts spins; Triaxialité; Modèle TAC; Modèle CNS; Nuclear structure; High spins; Triaxiality; Shape cohexistence; Isomeric states; Nuclear reactions; Coincidences, DCA ratios; CNS, TAC models

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

APA (6^th Edition):

Zerrouki, T. (2015). Triaxialité et coexistence de forme dans les noyaux proches de la fermeture de couche N = 82 : évolution de forme et rotation magnétique dans ¹⁴¹Nd : Triaxiality and shape coexistence in nuclei near N=82 shell closure : shape evolution and magnetic rotation in ¹⁴¹Nd. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2015PA112069

Chicago Manual of Style (16^th Edition):

Zerrouki, Thileli. “Triaxialité et coexistence de forme dans les noyaux proches de la fermeture de couche N = 82 : évolution de forme et rotation magnétique dans ¹⁴¹Nd : Triaxiality and shape coexistence in nuclei near N=82 shell closure : shape evolution and magnetic rotation in ¹⁴¹Nd.” 2015. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed April 15, 2021. http://www.theses.fr/2015PA112069.

MLA Handbook (7^th Edition):

Zerrouki, Thileli. “Triaxialité et coexistence de forme dans les noyaux proches de la fermeture de couche N = 82 : évolution de forme et rotation magnétique dans ¹⁴¹Nd : Triaxiality and shape coexistence in nuclei near N=82 shell closure : shape evolution and magnetic rotation in ¹⁴¹Nd.” 2015. Web. 15 Apr 2021.

Vancouver:

Zerrouki T. Triaxialité et coexistence de forme dans les noyaux proches de la fermeture de couche N = 82 : évolution de forme et rotation magnétique dans ¹⁴¹Nd : Triaxiality and shape coexistence in nuclei near N=82 shell closure : shape evolution and magnetic rotation in ¹⁴¹Nd. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2015. [cited 2021 Apr 15]. Available from: http://www.theses.fr/2015PA112069.

Council of Science Editors:

Zerrouki T. Triaxialité et coexistence de forme dans les noyaux proches de la fermeture de couche N = 82 : évolution de forme et rotation magnétique dans ¹⁴¹Nd : Triaxiality and shape coexistence in nuclei near N=82 shell closure : shape evolution and magnetic rotation in ¹⁴¹Nd. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2015. Available from: http://www.theses.fr/2015PA112069

Université Paris-Sud – Paris XI

9. Léguillon, Romain. Triaxialité et isomèrisme à hauts spins dans les noyaux proches de la fermeture de couche N = 82 : Triaxiality and seniority isomeric states in nuclei near the N = 82 shell closure.

Degree: Docteur es, Physique, 2013, Université Paris-Sud – Paris XI

URL: http://www.theses.fr/2013PA112223

► L'existence de noyaux triaxiaux a fait l'objet d'un débat de longue date. La possibilité de la triaxialité mole et rigide a été proposée très tôt,… (more)

▼ L'existence de noyaux triaxiaux a fait l'objet d'un débat de longue date. La possibilité de la triaxialité mole et rigide a été proposée très tôt, et de nombreuses études théoriques et expérimentales ont été consacrées à ce phénomène intrigant. Plus récemment, deux marqueurs uniques de la triaxialité dans les noyaux ont été intensivement étudiés : le mouvement d'oscillation de l'axe de rotation (wobbling) et la chiralité dynamique. Ces types exotiques de mouvement ont été observées dans des régions spécifiques du tableau nucléaire : le mouvement d'oscillation dans les noyaux de Lu impair-pair avec A ~ 160, la chiralité principalement dans les noyaux impair-impair et pair-impair avec A ~ 130. Nous avons récemment étudié les noyaux de Nd à très hauts spins et identifié plusieurs bandes, qui ont été interprétées comme la manifestation de divers types de mouvement collectif : rotation suivant un axe incliné, rotation suivant les axes longs et courts, mouvement de wobbling et bandes chirales. Un autre phénomène révélé par nos résultats récents sur les noyaux de Nd avec seulement quelques trous neutroniques par rapport à la fermeture de couche N = 82, est la coexistence de forme. En effet, ces noyaux sont prévus pour avoir des isomères de hauts spins construis sur une forme sphérique, coexistant avec des bandes triaxiales, ou des formes très voire super-déformées . Ma thèse se compose de deux expériences. Tout d'abord, j'ai préparé, exécuté et analysé une expérience réalisée au « Research Center of Nuclear Physics » (RCNP) de l' Université d'Osaka . Cette expérience visait à étudier les isomères de hauts spins et à développer les schémas de niveaux des noyaux de 135La, 136La et 136Ba. Nous avons utilisé un faisceau radioactif de 17N de 80 MeV créé par la réaction directe de 18O sur une cible 9Be et sélectionné à l'aide d'un spectromètre achromatique. Le faisceau radioactif de 17N bombardait une cible de 124Sn de 20 mg/cm2 d'épaisseur pour produire les noyaux d'intérêt par une réaction de fusion-évaporation. Cette thèse présente les résultats obtenus pour le 135La, qui comprennent la construction et la discussion du schéma de niveau et la mesure de la durée de vie de deux isomères connus. La deuxième partie de la thèse consiste en l'analyse de deux expériences différentes réalisée en utilisant la même combinaison de faisceau-cible 48Ca + 96Zr à une énergie légèrement différentes et deux dispositifs expérimentaux différents, EUROBALL et JUROGAM II + RITU + GREAT, pour étudier les isotopes du néodyme de 138Nd à 141Nd. Mon travail a été axé sur les noyaux pair-pair de 138Nd et 140Nd, avec un accent particulier sur le 140Nd. La multitude de bandes de spin élevé observées dans ce noyau sont discutées dans le cadre du modèle « Cranked Nilsson - Strutinsky » (CNS) et du modèle « Tilted Axis Cranking » (TAC). Les bandes de hauts spins observées dans les noyaux de 138-141Nd sont toutes interprétées comme basées sur un minimum d'énergie associé à une déformation triaxiale. Elles représentent donc un fort soutien à l'existence de la… Advisors/Committee Members: Petrache, Costel (thesis director).

Subjects/Keywords: Structure nucléaire; Hauts spins; Triaxialité; Coexistence de forme; États isomériques; Réactions nucléaires; Faisceaux radioactifs; Coïncidences, rapport DCO; Mesure de temps de vie; Méthode du déplacement du centroid; Modèles CNS, TAC; Nuclear structure; High spins; Triaxiality; Shape cohexistence; Isomeric states; Nuclear reactions; Radioactive beams; Coincidences, DCA ratios; Lifetime measurements; Centroid shift method; CNS, TAC models

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

APA (6^th Edition):

Léguillon, R. (2013). Triaxialité et isomèrisme à hauts spins dans les noyaux proches de la fermeture de couche N = 82 : Triaxiality and seniority isomeric states in nuclei near the N = 82 shell closure. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2013PA112223

Chicago Manual of Style (16^th Edition):

Léguillon, Romain. “Triaxialité et isomèrisme à hauts spins dans les noyaux proches de la fermeture de couche N = 82 : Triaxiality and seniority isomeric states in nuclei near the N = 82 shell closure.” 2013. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed April 15, 2021. http://www.theses.fr/2013PA112223.

MLA Handbook (7^th Edition):

Léguillon, Romain. “Triaxialité et isomèrisme à hauts spins dans les noyaux proches de la fermeture de couche N = 82 : Triaxiality and seniority isomeric states in nuclei near the N = 82 shell closure.” 2013. Web. 15 Apr 2021.

Vancouver:

Léguillon R. Triaxialité et isomèrisme à hauts spins dans les noyaux proches de la fermeture de couche N = 82 : Triaxiality and seniority isomeric states in nuclei near the N = 82 shell closure. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2013. [cited 2021 Apr 15]. Available from: http://www.theses.fr/2013PA112223.

Council of Science Editors:

Léguillon R. Triaxialité et isomèrisme à hauts spins dans les noyaux proches de la fermeture de couche N = 82 : Triaxiality and seniority isomeric states in nuclei near the N = 82 shell closure. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2013. Available from: http://www.theses.fr/2013PA112223

Universiteit Utrecht

10. Damme, R. van. Phase and vacancy behaviour of hard slanted cubes: a quantitative analysis on the influence of shape.

Degree: 2016, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/335293

► In this thesis, we study the phase and vacancy behaviour of hard slanted cubes (right rhombic prisms) as a function of their shape, defined through… (more)

Subjects/Keywords: Cube; Cubic; Rhomb; Rhombic; Monte Carlo; Monte; Carlo; MC; Vacancy; Vacancies; Hard cube; free energy; shape; shape switch; switch; phase behaviour; phase diagram; slant; slanted cube; tilt; tilted cube; isotension; isotension-isothermal ensemble; Einstein integration; Frenkel-Ladd; Einstein molecule; crystal; rhombic crystal; sheared cubic; random tiling; random; tiling; separating axis; equation of state; simulation; physics; colloid; computational; biased Monte Carlo; biasing; solid; coexistence

Record Details Similar Records Cite « Share

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

APA (6^th Edition):

Damme, R. v. (2016). Phase and vacancy behaviour of hard slanted cubes: a quantitative analysis on the influence of shape. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/335293

Chicago Manual of Style (16^th Edition):

Damme, R van. “Phase and vacancy behaviour of hard slanted cubes: a quantitative analysis on the influence of shape.” 2016. Masters Thesis, Universiteit Utrecht. Accessed April 15, 2021. http://dspace.library.uu.nl:8080/handle/1874/335293.

MLA Handbook (7^th Edition):

Damme, R van. “Phase and vacancy behaviour of hard slanted cubes: a quantitative analysis on the influence of shape.” 2016. Web. 15 Apr 2021.

Vancouver:

Damme Rv. Phase and vacancy behaviour of hard slanted cubes: a quantitative analysis on the influence of shape. [Internet] [Masters thesis]. Universiteit Utrecht; 2016. [cited 2021 Apr 15]. Available from: http://dspace.library.uu.nl:8080/handle/1874/335293.

Council of Science Editors:

Damme Rv. Phase and vacancy behaviour of hard slanted cubes: a quantitative analysis on the influence of shape. [Masters Thesis]. Universiteit Utrecht; 2016. Available from: http://dspace.library.uu.nl:8080/handle/1874/335293

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Open Access Theses and Dissertations