To see the other types of publications on this topic, follow the link: IsoSPI.
Dissertations / Theses on the topic 'IsoSPI'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'IsoSPI.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Malachowska, Julia, and Miko Nore. "Emulation of Analog Front-End isoSPI communication for Battery Management Systems." Thesis, KTH, Mekatronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297789.
Full textAbstract:
This study aims to investigate how an emulator could be developed as a testing tool for Battery Management Systems (BMS) by emulating the Analog Frontend (AFE) circuit communicating with a control unit for monitoring of LithiumIon Batteries. All of the research was conducted in the context of the company Northvolt. By analysing data collected through a questionnaire, it was evident that an emulator testing tool could potentially make the BMS development process significantly more efficient. A demonstrator was developed as a part of the study. It fulfilled almost all of the requirements initially stated, but required the control unit to send commands in a fixed sequence, which the current BMS control unit did not. A fixed sequence would however enable the incorporation of the developed emulator, as well as introducing other advantages such as predictability. The study showed that the most important factor to consider for developing an AFE communication emulator for BMS testing was robustness and repeatability of the timings of the communication signals.Syftet med denna studie var att undersöka hur ett testverktyg baserat på en emulator skulle kunna utvecklas för batteristyrsystem. Studien genomfördes på batteriföretaget Northvolt. Genom att analysera data insamlad via ett frågeformulär framgick det tydligt att ett testverktyg baserat på en emulator hade god potential att göra utvecklingsprocessen av batteristyrsystem mer effektiv. En prototyp utvecklades som en del av studien. Denna uppfyllde nästan alla de initialt uppsatta kraven, men var anpassad för kommunikation i en fix sekvens, till skillnad från det aktuella systemet hos företaget. Via studien fann man att implementationen av en fix kommunikationssekvens skulle medföra önskvärda egenskaper hos systemet såsom förutsägbarhet. Vidare visade studien att den viktigaste faktorn att ta i beaktning för utveckling av en emulator var robusthet och repeterbarhet hos timingen av kommunikationssignalerna. Detta eftersom kommunkationen mellan enheter förlitar sig på korrekt timing av varje skickad bit för korrekt inlästa meddelanden.
2
MALACHOWSKA, JULIA, and MIKO NORE. "Emulation of Analog Front-End isoSPI communication for Battery Management Systems." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299264.
Full textAbstract:
This study aims to investigate how an emulator could be developed as a testing tool for Battery Management Systems (BMS) by emulating the Analog Front-end (AFE) circuitcommunicating with a control unit for monitoring of Lithium-Ion Batteries. All of the research was conducted in the context of the company Northvolt. By analysing data collected through a questionnaire, it was evident that an emulator testing tool could potentially make the BMS development process significantly more efficient. A demonstrator was developed as a part of the study. It fulfilled almost all of the requirements initially stated, but required the control unit to send commands in a fixed sequence, which the current BMS control unit did not. A fixed sequence would however enable the incorporation of the developed emulator, as well as introducing other advantages such as predictability. The study showed that the most important factor to consider for developing an AFE communication emulator for BMS testing was robustness and repeatability of the timings of the communication signals.Syftet med denna studie var att undersöka hur ett testverktyg baserat på en emulator skulle kunna utvecklas för batteristyrsystem. Studien genomfördes på batteriföretaget Northvolt. Genom att analysera data insamlad via ett frågeformulär framgick det tydligt att ett testverktyg baserat på en emulator hade god potential att göra utvecklingsprocessen av batteristyrsystem mer effektiv. En prototyp utvecklades som en del av studien. Denna uppfyllde nästan alla de initialt uppsatta kraven, men var anpassad för kommunikation i en fix sekvens, till skillnad från det aktuella systemet hos företaget. Via studien fann man att implementationen av en fix kommunikationssekvens skulle medföra önskvärda egenskaper hos systemet såsom förutsägbarhet. Vidare visade studien att den viktigaste faktorn att ta i beaktning för utveckling av en emulator var robusthet och repeterbarhet hos timingen av kommunikationssignalerna. Detta eftersom kommunkationen mellan enheter förlitar sig på korrekt timing av varje skickad bit för korrekt inlästa meddelanden.
3
Juillet, Olivier. "Symetries nucleaires a faible isospin." Caen, 1999. http://www.theses.fr/1999CAEN2057.
Full textAbstract:
Avec le developpement des faisceaux radioactifs, un interet particulier est actuellement porte aux noyaux exotiques riches en protons. Ces structures offrent en effet la possibilite de developper une superfluidite proton-neutron dont l'importance vis a vis des correlations d'appariement entre nucleons identiques fait l'objet de nombreuses etudes theoriques. Le travail presente propose precisement d'aborder ce probleme dans le cadre d'une approche algebrique basee sur une symetrie su(4) de wigner combinant les degres de liberte de pseudo-spin et d'isospin. Apres avoir repris en detail les implementations de la theorie des groupes en mecanique quantique, la pertinence de la classification pseudo-su(4) est directement montree au niveau des etats realistes du modele en couches. Ses consequences au niveau des masses et des transitions de decroissance sont egalement analysees. Sa realisation partielle en bosons de moment orbital nul est de plus utilisee pour mettre en evidence un certain nombre de phenomenes physiques specifiques a la ligne n = z comme la condensation en structures de type ou la destruction par le potentiel spin-orbite des correlations superfluides isoscalaires. Enfin, un autre schema de bosonisation incluant des degres de liberte quadrupolaires (modele ibm-4) est teste pour la premiere fois en diagonalisant un hamiltonien complet deduit d'une interaction realiste du modele en couches. La qualite des resultats obtenus, plus particulierement pour les noyaux impair-impair, permet raisonnablement d'envisager l'utilisation de cette approximation en bosons comme alternative aux approches fermioniques standard pour elucider la structure collective de la ligne exotique n z = 28-50.
4
Farnea, Enrico. "Spectroscopic studies of isospin mixing in 64Ge." Thesis, University of Surrey, 2001. http://epubs.surrey.ac.uk/844488/.
Full textAbstract:
The high-spin states of the nucleus 64Ge have been investigated using the GASP and the EUROBALL arrays of high-purity germanium detectors. In order to achieve the required experimental sensitivity, special selecting devices were used, namely a highly efficient array of liquid scintillators to detect neutrons and the ISIS Si-ball to detect light charged particles, which has been developed in the present work. A detailed decay scheme for 64Ge has been deduced, assigning spins and parities to the levels through a Directional Correlation from Oriented states analysis, an Angular Distribution analysis and a Polarization Correlation from Oriented states analysis. The character of an intense 1665 keV transition, previously reported as a stretched electric dipole with a small multipole mixing ratio, has been established as an electric dipole with a large multipole mixing ratio. The electric dipole strength has been measured using EUROBALL coupled to an early implementation of the EUCLIDES Si-ball and with the Koln plunger device, allowing an experimental estimate of the isospin mixing probability in 64Ge.
5
Lam, Yek Wah. "Isospin symmetry breaking in sd shell nuclei." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14446/document.
Full textAbstract:
Dans cette thèse, nous avons développé une approche microscopique de la description des effets de la brisure de symétrie d’isospin dans les noyaux de la couche sd. Le travail est effectué dans le cadre du modèle en couches.Nous avons ajouté à un Hamiltonien nucléaire traditionnel, qui conserve l’isospin, l’interaction de Coulomb et le potentiel de type Yukawa d'échange de mésons pour modéliser les forces nucléaires dépendantes de la charge. La base de données sur les coefficients expérimentaux de l'équation des multiplets de masse isobariques (IMME) a été mise au point dans le cadre de cette thèse et a été utilisée pour ajuster les paramètres de l’hamiltonien. L'hamiltonien ainsi construit fournit une description théorique très précise du mélange d’isospin dans les états nucléaires. Nous montrons la pertinence de cette approche dans deux applications importantes : (i) le calcul des amplitudes d'émission de proton interdites par isospin, essentiels dans le cadre d’astrophysique nucléaire et (ii) le calcul de corrections (dues au mélange d'isospin) aux transitions bêta superpermises du type Fermi, cruciales pour les tests des symétries fondamentales du Modèle Standard de l’interaction électrofaibleIn the thesis, we develop a microscopic approach to describe theisospin-symmetry breaking effects in sd-shell nuclei.The work is performed within the nuclear shell model.A realistic isospin-conserving Hamiltonian is supplementedby a charge-dependent part consisting of the Coulomb interaction andYukawa-type meson exchange potentials to model charge-dependent forces ofnuclear origin. The extended database of the experimental isobaric mass multiplet equation coefficients is compiled during the thesis work and is used in a fit of the Hamiltonian parameters.The constructed Hamiltonian provides an accurate theoretical description ofthe isospin mixing nuclear states. A specific behaviour of the IMME coefficients have been revealed.We present two important applications (i) calculations of isospin-forbiddenproton emission amplitudes, which is often of interest for nuclearastrophysics, and (ii) calculation on corrections to nuclear Fermi beta decay, which is crucial for the tests of fundamental symmetries of the weak interaction
6
Portelli, Antonin. "Nonpertubative quantum chromodynamics and isospin symmetry breaking." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4110.
Full textAbstract:
Depuis les années 1930, on sait que le noyau des atomes est composé de deux types de particules: les protons et les neutrons. Ces deux particules sont très similaires: d'une part le neutron est subtilement plus lourd (un pour mille) que le proton et d'autre part le proton porte une charge électrique positive tandis que le neutron est neutre. La petite différence de masse entre le neutron et le proton fourni l'énergie suffisante pour autoriser désintégration où un neutron se désintègre en un proton en émettant un électron et un anti-neutrino électronique. Aussi, le fait que le proton ne se désintègre pas assure la stabilité de l'atome d'hydrogène. De plus, on sait empiriquement que les paramètres de la désintégration déterminent la composition des noyaux d'atomes stables plus lourds que l'hydrogène. Il est donc raisonnable de penser que si la différence de masse entre le neutron et le proton était de signe opposé ou seulement légèrement différente, l'Univers visible serait surement très différent de celui que l'on connait. Il est donc essentiel de comprendre l'origine de cette différence de masse à partir des principes premiers de la physique. C'est à ce problème, et à des problèmes liés à celui-ci, qu'essaye de répondre ce travail. Dans la compréhension actuelle de la physique, les neutrons et les protons sont des particules composées de particules élémentaires appelées quark up (symbole u) et quark down (symbole d). Le proton est un état lié uud et le neutron est un état lié udd. Les quarks up et down sont deux particules similaires: elles sont toutes deux légères (de l'ordre de quelques MeV) et leurs charges électriques sont différentes
7
Whittamore, Zakary. "Isospin-violating dark matter and direct detection experiments." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123143.
Full textAbstract:
Hints of direct detection of dark matter have been presented by the DAMA, CoGeNT, and CRESST collaborations, despite a number of null results that seem to contradict such claims. Although standard spin-independent dark matter is not capable of reconciling the results, dark matter models containing isospin-violating couplings have shown promise in solving the issues surrounding direct detection of dark matter. Inelastic or momentum-dependent scattering dark matter has also been shown to help alleviate these tensions. In light of the 2012 XENON100 observations, updated analysis of surface event contamination at CoGeNT, revision of the energy resolution employed by XENON10, and new results from the CDMS-II silicon detectors, we study the extent to which spin-independent, spin-dependent, and combined models of isospin-violating dark matter are capable of explaining current direct detection data. Moreover, we explore the effect of an energy-dependent sodium quenching factor $Q_{\rm Na}$ for fitting the DAMA observations, and give an isospin-violating prediction for XENON1T. In addition to the usual analysis involving phase space plots, we investigate a halo-independent model of dark matter in the space of minimum velocities required for a dark matter particle to scatter off a given nucleus. For the first time, such an analysis is performed for models of dark matter which embrace both inelastic and isospin-violating couplings, as well as for dark matter with momentum- and spin dependent interactions. With respect to the models considered herein, our results do not support a dark matter interpretation of direct detection data in either the standard or halo-independent formalisms.Conseils de détection directe de la matière noire ont été présentés par les DAMA, CoGeNT, et CRESST collaborations, malgré un certain nombre de résultats nuls qui semblent contredire ces allégations. Bien que la norme matière noire indépendante du spin n'est pas capable de concilier la résultats, la matière noire modèles contenant couplages de isospin-violation ont montré des résultats prometteurs dans résolution des problèmes de détection directe de la matière noire. Diffusion inélastique ou dynamique dépendant de la matière noire a également été démontré que aider à atténuer ces tensions. À la lumière des observations XENON100 2012, analyse actualisée de la contamination de l' événement de surface à CoGeNT, la révision de la résolution de l'énergie utilisée par XENON10, et de nouveaux résultats provenant des détecteurs de silicium CDMS-II, nous étudier la mesure dans laquelle indépendante du spin, dépendant du spin, et des modèles combinés de la matière noire isospin-violation sont capables d'expliquer les données de détection directs actuels. De plus, nous explorons l'effet d'une trempe de sodium dépendant de l'énergie facteur $Q_{\rm Na}$ pour le montage des observations DAMA, et de donner une prévision de isospin-violation de XENON1T. En plus de l'analyse habituelle impliquant des parcelles de l'espace de phase, nous étudions un modèle de halo-indépendant de la matière noire dans l'espace des vitesses minimales requises pour une particule de matière noire se disperser hors d'un noyau donné. Pour la première fois, une telle analyse est effectuée pour les modèles de matière noire qui embrassent les deux couplages élastiques et isospin-violation, ainsi que de la matière noire avec des interactions dépendant du dynamique et spin. En ce qui concerne les modèles considérés ici, nos résultats ne soutiennent pas une question d'interprétation sombre de données de détection directe soit dans la norme ou formalismes halo-indépendant.
8
Bell, Elizabeth. "N/Z equilibration." Texas A&M University, 2003. http://hdl.handle.net/1969.1/2306.
Full textAbstract:
The N/Z, or ratio of neutron to proton, degree of freedom may be used to study
intermediate energy nuclear collisions to give information about the origin of emitted
collision fragments. Establishing under what conditions the onset of N/Z equilibrium
occurs will give a better understanding of the physics of the equation of state through the
use of simulation codes. If the nuclear equation of state can be elucidated in terms of the
N/Z dependent component and how the N/Z dependent component varies with density,
then the equilibrium ratio of protons to neutrons inside high density neutron stars can be
inferred, allowing for prediction of cooling rates and supernovae mechanisms.
In the current study, isotopic and isobaric ratios at thetalab=40o with cuts of 10% and
20% most central events, respectively, are studied for their N/Z equilibration signals.
Light charged particles, or LCPs, are found to be emitted from systems which have not
yet fully N/Z combined; the fragments with A=3 are emitted from the least equilibrated
systems. Intermediate mass fragments, or IMFs, are seen to be emitted by N/Z
equilibrated sources, within statistical error bars.
The N/Z tracer method is used with ratios of isotopes and isobars to see how the
amount of nuclear stopping or N/Z mixing changes as a function of the centrality of the
event. The N/Z observable is used to reinvestigate earlier findings of the isotope and
isobar ratio observables and shows the progression (or lack of it, in some cases) of the
N/Z equilibration. This observable has proven to be a clear and sensitive tool to use
when considering the differences in N/Z mixing of the systems at two energies.
9
Titov, A. I., T. I. Gulamov, and Burkhard Kämpfer. "Neutral roh-meson properties in an isospin-asymmetric pion medium." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-32202.
Full text
10
Marini, Paola <1981>. "Isospin dependence of the Ar+Ni fusion-evaporation cross section." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1532/.
Full textAbstract:
The fundamental goal of this thesis is the determination of the isospin dependence of the Ar+Ni fusion-evaporation cross section. Three Ar isotope beams, with energies of about 13AMeV, have been accelerated and impinged onto
isotopically enriched Ni targets, in order to produce Pd nuclei, with mass number varying from 92 to 104. The measurements have been performed by the high performance 4pi detector INDRA, coupled with the magnetic spectrometer VAMOS. Even if the results are very preliminary, the obtained fusion-evaporation cross sections behaviour gives a hint at the possible isospin dependence of the fusion-evaporation cross sections.
11
Titov, A. I., T. I. Gulamov, and Burkhard Kämpfer. "Neutral roh-meson properties in an isospin-asymmetric pion medium." Forschungszentrum Rossendorf, 1994. https://hzdr.qucosa.de/id/qucosa%3A22047.
Full text
12
Velardita, Simone. "Isospin transport phenomena in nuclear reactions in the Fermi energy range." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18418/.
Full textAbstract:
This thesis work has been done within the NUCL-EX group of the INFN group II. The work has consisted of the preparation and the first measurement of the coupled apparatus INDRA-FAZIA, in the identification of data obtained in the previous measurement with FAZIA and in the analysis of data that were already calibrated in a precedent measurement with INDRA coupled with the spectrometer VAMOS. The FAZIA apparatus was built with a collaboration that involves more than 10 institutions in six different countries. A long phase of research and development was necessary to obtain what today can be considered one of the best apparatus for measurements of charged particles emitted in nuclear reactions. The measurement made with INDRA-VAMOS was analyzed in order to verify the isospin effects (N/Z content) in peripheral and semi-peripheral reactions Ca(40,48)+Ca(40,48) at 35 MeV/u. In these collisions, the transport models predict the formation of a low-density neck between two hot fragments kinematically similar to the projectile (PLF) and target (TLF). The isotopic identification of PLF provided by VAMOS, together with those of light charged particles (LCP) revealed in coincidence with INDRA allow, through their correlation, to reconstruct the primary fragment. During the reconstruction phase, the mass number (A) is made without the emitted neutron contribution, because these are not detected. To estimate the excitation of the source is necessary to make some assumption about the evaporated neutrons, to obtain the most realistic estimate. Finally, in order to extrapolate information about the energy symmetry term of the Nuclear Equation of State, it is shown the study of the width of isotopic distributions. The preliminary result obtained is the trend of the symmetry energy coefficient (Csym) as a function of the charge of the reconstructed primary fragment, which is dependent on the surface term, present in the liquid drop model of the nucleus.
13
Wolfe, Carl Eric. "Calculation of some selected isospin-breaking observables in the standard model." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0002/NQ43456.pdf.
Full text
14
Neto, Ettore Baldini. "Simetrias dinâmicas e energias de ligação de núcleos com N = Z." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-11122013-170410/.
Full textAbstract:
Neste trabalho é apresentado um modelo algébrico para o cálculo de energias de ligação de núcleos pesados com N = Z baseado nas versões invariantes por isospin do Modelo de Bósons interatuantes (IBM). Com a utilização de uma interação adequada para a descrição dos modos isoescalar e isovetorial do emparelhamento nuclear adicionada àquelas interações que descrevem globalmente uma dada região de massa, foram ajustados os parâmetros da hamiltoniana e calculados núcleos com N = Z ao longo das camadas sd e pf. Deste modo, pôde-se fazer algumas predições, para suas massas do estado fundamental e para estados excitados, que oferecem um desafio às novas gerações de feixes radiativos que estão por vir.In this work we present an algebraic model for calculating the binding energies of heavy nuclei with the same number of protons and neutrons which is based in the isospin invariant versions of the Interacting Boson Model (IBM). With an adequate interaction for the description of the isoscalar and isovector pairing modes of the residual nuclear interaction added to those terms responsible for the bulk properties of a given mass region, we have fitted the parameters of our algebraic Hamiltonian and have calculated nuclei with N=Z along the sd and pf shells. Therefore we were able to make some predictions, for their ground state masses as well as for the excited states, which offer a challenge to the new generations of radioactive nuclear beams.
15
Kämpfer, Burkhard, T. I. Gumalov, and A. I. Titov. "Asymmetry of the Dielectron Emission Rate in an Isospin-Asymmetric Pion Medium." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-31736.
Full textAbstract:
Asymmetry of the Dielectron Emission Rate in an Isospin-Asymrnetric Pion Medium T.I. GULANOVA,1 A. I. TITOV Bogoliubov Theoretical Laboratory, Joint Institute for Nuclear Research, 141980 Dubna, Russia B. Kämpfer Research Center Rossendorf, Institute for Nuclear and Hadron Physics, PF 510119, 01314 Dresden, Germany Institute for Theoretical Physics, Technical University Dresden, Mommsenstr. 13, 01062 Dresden, Germany Abstract The dielectron emission by pion annihilation in an isospin-asymmetric pion gas at finite temperature is considered. Due to the differente between the longitudinal and tramverse parts of the in-medium p meson self-energy a specific asymmetry of the rates is caused for electron pairs with relative momenta perpendicular or parallel to the total pair momentum. This asymmetry may be considered as a sensitive signal of in-medium-modifications of the p properties. 1Permanent- address: Physical and Technical Institute of Uzbek Academy of Sciences, 700084 Tashkent, RepubIic Uzbekistan
16
Kämpfer, Burkhard, T. I. Gumalov, and A. I. Titov. "Asymmetry of the Dielectron Emission Rate in an Isospin-Asymmetric Pion Medium." Forschungszentrum Rossendorf, 1995. https://hzdr.qucosa.de/id/qucosa%3A22000.
Full textAbstract:
Asymmetry of the Dielectron Emission Rate in an Isospin-Asymrnetric Pion Medium T.I. GULANOVA,1 A. I. TITOV Bogoliubov Theoretical Laboratory, Joint Institute for Nuclear Research, 141980 Dubna, Russia B. Kämpfer Research Center Rossendorf, Institute for Nuclear and Hadron Physics, PF 510119, 01314 Dresden, Germany Institute for Theoretical Physics, Technical University Dresden, Mommsenstr. 13, 01062 Dresden, Germany Abstract The dielectron emission by pion annihilation in an isospin-asymmetric pion gas at finite temperature is considered. Due to the differente between the longitudinal and tramverse parts of the in-medium p meson self-energy a specific asymmetry of the rates is caused for electron pairs with relative momenta perpendicular or parallel to the total pair momentum. This asymmetry may be considered as a sensitive signal of in-medium-modifications of the p properties. 1Permanent- address: Physical and Technical Institute of Uzbek Academy of Sciences, 700084 Tashkent, RepubIic Uzbekistan
17
Dickopp, Martin. "Measurement of the partial widths ratio Gamma(D * s + D + s pi 0)/Gamma(D * s + D + s gamma) at the BABAR experiment." [S.l. : s.n.], 2004. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11312542.
Full text
18
Titov, A. I., Burkhard Kämpfer, and T. I. Gulamov. "Rho Meson Self-Energy and Dielectron Emissivity in an Isospin-Asymmetric Pion Medium." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-31971.
Full text
19
Titov, A. I., Burkhard Kämpfer, and T. I. Gulamov. "Rho Meson Self-Energy and Dielectron Emissivity in an Isospin-Asymmetric Pion Medium." Forschungszentrum Rossendorf, 1995. https://hzdr.qucosa.de/id/qucosa%3A22023.
Full text
20
Mukwevho, Ndinannyi Justice. "Characterisation of the first 1/2+ excited state in 9B and isospin symmetry breaking studies in A = 9 nuclei." University of the Western Cape, 2019. http://hdl.handle.net/11394/6756.
Full textAbstract:
>Magister Scientiae - MScThe 9Be - 9B isospin doublet carries fundamental significance for both nuclear structure and nuclear astrophysics studies. The first excited 1/2+ state in 9Be is already well established. However, its isobaric analogue 1/2+ state in 9B has not been unambigously determined yet. Theoretically, two popular descriptions of the 9Bnucleus either use a cluster model with two unbound alpha particles held together by a covalent proton or using the shell model, as a 8Be core + proton in the sd shell. An experimental determination of the excitation energy of the first 1/2+ state in 9B will provide valuable information in validating the theoretical model that adequately describes such light unbound nuclei. Further, it will also provide a robust test of mirror (isospin) symmetry violations via measurements of mirror energy differences in the doublet. Although there have been several experimental attempts to characterize the first 1/2+ state in 9B several discrepancies still exist in reported values of the excitation energies. This thesis describes an experiment performed at iThemba LABS using the 9Be(3He,t)9B reaction to address the above issue. As a byproduct, the thesis also describes an additional determination of the excitation energy of the second J-pi = 1/2+, T = 3/2 state in 9B from the same experiment. This was performed in order to resolve a discrepancy related to the excitation energy of this state. The consequence of this measurement related to Isobaric Multiplet Mass Equation (IMME) for the excited T = 3/2, A = 9 quartet is discussed briefly.
21
Ueding, Martin [Verfasser]. "Three Pion Scattering at Maximal Isospin from Lattice QCD at Physical Mass / Martin Ueding." Bonn : Universitäts- und Landesbibliothek Bonn, 2021. http://d-nb.info/1227990359/34.
Full text
22
Razeira, Moises. "Naturalidade, quebra de simetria de isospin e a estrutura interna das estrelas de nêutrons." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/23231.
Full textAbstract:
Nesta tese, desenvolvemos um modelo efetivo para a matéria nuclear, com vistas à escrição de propriedades de estrelas de nêutrons e pulsares, por meio de uma formulação lagrangeana que busca exaurir o espaço de fase dos campos mesônicos por meio de um tratamento perturbativo que apresente alto grau de consistência com o conceito de naturalidade, de modo a aprimorarmos as predições dos tratamentos teóricos mais convencionais. Uma versão preliminar deste modelo efetivo, que contempla a presença, no setor bariônico, somente dos campos dos núcleons, é inicialmente apresentada, juntamente com a abordagem dos temas da naturalidade, da anomalia Nolen-Schiffer e da quebra de simetria de isospin na matéria nuclear. Ainda, com base na conservação de simetria quiral, apresentamos a predição da existência de um estado ressonante mesônico no setor escalar-isovetorial leve, estado este representado pelo campo ç. E então, baseados no conceito de naturalidade, desenvolvemos o modelo efetivo para a matéria nuclear supra mencionado. A versão do modelo efetivo inicialmente desenvolvido contempla acoplamentos entres os campos dos núcleons e dos mésons a, w,_,_e ç. Então apresentamos as predições do modelo para a anomalia Nolen-Schiffer e discutimos os resultados obtidos. Os resultados obtidos neste trabalho apresentam expressivo aprimoramento na descrição da anomalia Nolen-Schiffer quando comparados os correspondentes resultados do modelo MRWY desenvolvido recentemente por outros autores. Em primeiro lugar porque nossos resultados apresentam percentuais de melhoramento na descrição da anomalia Nolen-Schiffer que variam entre 80% e 320%. Em segundo lugar porque o ordenamento dos resultados obtidos em nosso trabalho está em conformidade com o ordenamento dos dados experimentais, diferentemente dos resultados apresentados no trabalho supra mencionado. Em especial, nossas predições para o ordenamento dos dados experimentais da anomalia Nolen-Schiffer (_ANS) contemplam o conhecido crescimento anômalo, ou seja, que _ANS não cresce necessariamente com o número de massa, pois _ANS é menor para os núcleos 39Ca-39 K em comparação aos núcleos 17F-17 O. Introduzimos também uma versão estendida do modelo anteriormente apresentado em que consideramos acoplamentos de natureza não-linear envolvendo o octecto fundamental bariônico e os campos dos mésons a, w,_,ç,_,a*, Ø. Denominamos esta formulação como modelo ZM modificado, adotando a sigla ZMM para caracterizá-lo. Utilizando procedimentos padrões da teoria quântica de campos, obtivemos então para o modelo ZMM a equação de estado para a matéria nuclear em equilíbrio ß e em equilíbrio ß generalizado. Os resultados obtidos indicam que a presença do méson_ implica na diminuição da assimetria de isospin no setor dos núcleons da estrela de nêutrons, ou seja, na diminuição da diferença do número de nêutrons e prótons do sistema. A inclusão do méson ç leva a uma diminuição da assimetria de isospin ainda maior, ou seja, sua presença é equivalente à uma amplificação da amplitude do méson_. Os resultados obtidos para o modelo ZMM indicam que a inclusão do méson_ e do estado ressonante ç no formalismo modifica os valores da massa máxima e do raio das estrelas de nêutrons. Finalmente derivamos uma formulação relativística para descrever o chamado processo Urca direto em matéria bariônica degenerada.Nossos resultados indicam que estrelas de nêutrons com massas superiores a MEN ~ 0,9M_, - que representa a massa estelar crítica, ou seja, a massa da estrela de nêutrons cuja densidade bariônica central atingiu a densidade crítica- , seriam resfriadas eficientemente e estariam fora da possibilidade de detecção por radiação térmica em poucos anos.In this thesis we developed an effective model for nuclear matter, with a view to the description of the properties of neutron stars and pulsars, using a lagrangean formulation which exhausts the phase space of the meson fields through a treatment that presents high level of consistency with the concept of naturalness, in order to improve the predictions of more conventional theoretical treatments. A preliminary version of this effective model, which includes the presence, in the baryon sector, only of the nucleon fields is initially presented and then we make a study on the themes of naturalness, Nolen-Schiffer anomaly and the broken symmetry of the nuclear isospin. Still, based on the conservation of chiral symmetry, we present the predictions for a new resonant meson state in the scalar-isovectorial sector, this state represented by the symbol ç. And then, based on the concept of naturalness, we developed the effective model for nuclear matter we mentioned above. The version of the effective model originally developed presents couplings between the fields of the nucleons and the a, w,_,_and ç meson fields. Then we present the predictions of the model for the Nolen-Schiffer anomaly and discuss the results. The results of this study show significant improvements in the description of the Nolen-Schiffer anomaly when compared to the corresponding results of the MRWY model developed recently by other authors. Firstly, because our results show a relevant improvement in the description of the Nolen-Schiffer anomaly that vary between 80 and 320 percent. Secondly, because the achievements of our work are in good accordance with experimental data, unlike the results presented in the work mentioned above. In particular, our predictions for the Nolen-Schiffer anomaly (_NSA) include the known anomalous growth, namely that _NSA does not necessarily grows with the nuclear mass, because _NSA is lower for the nuclei 39Ca-39K compared to the 17F-17 O nuclei. We have also introduced an extended version of the model previously presented involving the fundamental baryon octect and the a, w,_,ç,_,a*, Ø meson fields. We call this formulation as ZM modified model, adopting the acronym ZMM to characterize it. Using standard procedures of the quantum field theory, then we use the ZMM model to describe the equation of state for nuclear matter in ß and generalized ß equilibrium. The results of our approaches indicate that the presence of the_ meson increases the isospin asymmetry in the nucleon sector of the neutron star, this way reducing the difference in the number of neutrons and protons in the system. The inclusion of the resonant state ç leads to an increase of the asymmetry of isospin even greater, that is, their presence is equivalent to an amplification of the magnitude of _ meson. The results for the ZMM model indicate that the inclusion of the _ and ç meson states in the formalism modifies the values of the mass and radius of the neutron stars. Finally, we derive a relativistic formulation to describe the so called direct Urca process in barionic degenerated matter. Our results indicate that the neutron stars with mass greater than MNE~ 0.9M_, which represents the stellar critical mass (the mass of the neutron star whose baryon central density reached the critical density) would be cooled efficiently and be outside the possibility of detection by heat radiation in a few years.
23
Taniguchi, Nanae. "Measurement of branching fractions, isospin and CP-violating asymmetries for exclusive b → dγ modes." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/124374.
Full text
24
Owen, Patrick. "Measurement of branching fractions, isospin asymmetries and angular observables in exclusive electroweak penguin decays." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/24751.
Full textAbstract:
This thesis describes measurements of rare electroweak penguin decays performed with data collected by the Large Hadron Collider beauty experiment corresponding to 3 fb^{-1} of integrated luminosity. The purpose of these measurements is to search for physics beyond the theoretical framework known as the Standard Model (SM). Electroweak penguin decays are sensitive to virtual particles in extensions to the SM whose influence on the decay amplitude can be of similar strength to the SM contribution. The particular measurements that are described in this thesis are the differential branching fractions and isospin asymmetries of B -> K(*) μ^+ μ^- decays as well as the angular observables in B -> K μ^+ μ^- decays. Although results are consistent with the SM, all the branching fractions of B -> K(*) μ^+ μ^- decays tend to favour a lower value than theoretical predictions.
25
Helmes, Christopher [Verfasser]. "K-K and pi-K Scattering Lengths at Maximal Isospin from Lattice QCD / Christopher Helmes." Bonn : Universitäts- und Landesbibliothek Bonn, 2019. http://d-nb.info/1194464831/34.
Full text
26
Graeff, Clebson Abati. "Mistura de isospin em modelos de campo-médio relativísticos e o espalhamento de elétrons polarizados." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/100762.
Full textAbstract:
Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Física, Florianópolis, 2012Made available in DSpace on 2013-06-25T22:23:35Z (GMT). No. of bitstreams: 1 314267.pdf: 2155696 bytes, checksum: b5faabe3741556208d7a3bb7c8cf0894 (MD5)
Neste trabalho investigamos efeitos de mistura de isospin através da assimetria observada no espalhamento elástico de elétrons polarizados, para vários alvos nucleares ao longo da tabela periódica, desde 4He até 208Pb. Os cálculos para o espalhamento são realizados em uma aproximação de Born de ondas planas (PWBA) assim como de forma exata, utilizando uma expansão em ondas parciais (DWBA), levando-se em conta os fatores de forma dos nucleons, dados pela parametrização de Galster. Para decrever o núcleo utilizamos o Modelo de Walecka (QHD), onde incluímos os mésons sigma, omega, rho e delta, além da interação eletromagnética. Os efeitos da inclusão dos mésons rho e delta são de especial interesse devido a sua influência na mistura de isospin, juntamente com o campo eletromagnético. Comparamos os resultados utilizando dois tipos de lagrangeanas, uma contendo termos não-lineares e outra com acoplamentos dependentes da densidade bariônica. O modelo é resolvido em uma aproximação de Hartree, considerando-se simetria esférica, através de um cálculo auto-consistente utilizando uma expansão das funções de onda e potenciais nucleares em uma base de oscilador harmônico. As implicações da mistura de isospin na obtenção de parâmetros do Modelo Padrão, do fator de forma de estranheza para o nucleon e na determinação da chamada pele de nêutrons do núcleo, usando a técnica de espalhamento de elétrons polarizados, são analizadas.
Abstract : We investigate isospin mixing effects in the asymmetry as obtained through polarized elastic electron scattering, for selected nuclei from 4He to 208Pb. The scattering analysis is developed within a plane wave Born approximation (PWBA) as well as within a partial wave phase-shift analysis (DWBA), accounting for nucleon form factors, which are given by the Galster parametrization. To describe the nuclear structure, we use Walecka's Model (QHD), including the sigma, omega, rho and delta mesons as well as the electromagnetic interaction. The $\rho$ and $\delta$ meson effects are specially interesting once they should add a contribution for isospin mixing together with the electromagnetic field. We employ two type of lagrangeans, one including non-linear terms and another one which contains density dependent couplings. The model is solved in a Hartree approximation within spherical symmetry using a self-consistent calculation by means of an expansion of the nuclear wave functions and strong potentials in an harmonic oscillator basis. The implications of isospin mixing in the determination of some Standard Model parameters and the extraction of the strange nucleon form factor, as well as in the determination of the so called neutron skin, from polarized elastic electron scattering, is analized and discussed.
27
Guimaraes, Valdir. "Estudo da Estrutura dos Núcleos 17Ne e 13O pela reação de pick-up (3He, 6He)." Universidade de São Paulo, 1994. http://www.teses.usp.br/teses/disponiveis/43/43131/tde-05122013-110123/.
Full textAbstract:
The nuclear structme of 17Ne and 13O has been studied by the 20Ne(3He,6He)17Ne and 16O(3He,6He)13O reactions at 70 MeV and 80 MeV, respectively. Fifteen levels were identified, and angular distributions have been measured for nine of these levels in 17Ne, while for 13O eighteen levels were identified, but angular distributions were obtained for only ten levels. The observed transferred angular momentum dependence of these angular distributions allowed spin-parity assignments. The T= 3/2 quartet analog states in mass A=17 have been completed for six levels. The results of the isobaric multiplet mass equation analysis show a slight linear dependence of the b and c coefficients on the excitation energy. It was found that the coefficients for the positive parity states do not follow the systematics of the negative parity states. The absolute values of the b and c coefficients are larger for the positive parity states. An analysis in terms of Coulomb energy displacement indicates a possible configuration mixing or core polarization effect in these states. The d coefficient also has a large deviation from zero, only for the positive parity states indicating a possible expansion of the radial wavefunction or some isospin symmetry breaking effects. Further detailed theoretical interpretation of these effects may bring valuable information about the configuration and structure of these states. The leveis in 13O were measured with good energy resolution, and thus, it was possible to identify the first excited state unambiguously. However, if one identifies this state as the analog of the known first excited state in the mirror nucleus 13B, this leads to one of the largest level shifts known in literature.The nuclear structme of 17Ne and 13O has been studied by the 20Ne(3He,6He)17Ne and 16O(3He,6He)13O reactions at 70 MeV and 80 MeV, respectively. Fifteen levels were identified, and angular distributions have been measured for nine of these levels in 17Ne, while for 13O eighteen levels were identified, but angular distributions were obtained for only ten levels. The observed transferred angular momentum dependence of these angular distributions allowed spin-parity assignments. The T= 3/2 quartet analog states in mass A=17 have been completed for six levels. The results of the isobaric multiplet mass equation analysis show a slight linear dependence of the b and c coefficients on the excitation energy. It was found that the coefficients for the positive parity states do not follow the systematics of the negative parity states. The absolute values of the b and c coefficients are larger for the positive parity states. An analysis in terms of Coulomb energy displacement indicates a possible configuration mixing or core polarization effect in these states. The d coefficient also has a large deviation from zero, only for the positive parity states indicating a possible expansion of the radial wavefunction or some isospin symmetry breaking effects. Further detailed theoretical interpretation of these effects may bring valuable information about the configuration and structure of these states. The leveis in 13O were measured with good energy resolution, and thus, it was possible to identify the first excited state unambiguously. However, if one identifies this state as the analog of the known first excited state in the mirror nucleus 13B, this leads to one of the largest level shifts known in literature.
28
Dickopp, Martin. "Measurement of the Partial Widths Ratio Gamma(Ds*+ -> Ds+ pi0) / Gamma(Ds*+ -> Ds+ gamma) at the BABAR Experiment." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1090940165906-60184.
Full textAbstract:
Unter Benutzng von 90.4/fb Daten, die das BABAR-Experiment in den Jahren 1999 bis 2002 genommen hat, wurden die Zerfälle Ds*+ -> Ds+ pi0 und Ds*+ -> Ds+ gamma mit zwei verschiedenen Methoden rekonstruiert. Die Rekonstruktions-Effizienzen wurden mittels Signal-Monte Carlo-Ereignissen und D*0-Zerfällen ermittelt. Auf diese Weise wurde das Partialbreiten-Verhältnis Gamma(Ds*+ -> Ds+ pi0) / Gamma(Ds*+ -> Ds+ gamma) auf vier verschiedene Weisen gemessen. Zusätzlich wurde das Partialbreiten-Verhältnis Gamma(D*0 -> D0 pi0) / Gamma(D*0 -> D0 gamma) gemessenUsing 90.4/fb of data taken at the BABAR experiment in the years 1999 to 2002, the decays Ds*+ -> Ds+ pi0 and Ds*+ -> Ds+ gamma have been reconstructed with two different methods. Signal Monte Carlo events as well as D*0 decays have been used to determine the reconstruction efficiencies. Thereby, the partial widths ratio Gamma(Ds*+ -> Ds+ pi0) / Gamma(Ds*+ -> Ds+ gamma) has been measured in four different ways. Additionally, the partial widths ratio Gamma(D*0 -> D0 pi0) / Gamma(D*0 -> D0 gamma) has been measured
29
Nowakowski, Daniel Verfasser], Michael [Akademischer Betreuer] Buballa, and Jochen [Akademischer Betreuer] [Wambach. "Inhomogeneous chiral symmetry breaking in isospin-asymmetric strong-interaction matter / Daniel Nowakowski ; Michael Buballa, Jochen Wambach." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2017. http://d-nb.info/1131254228/34.
Full text
30
Li, Jia Jie. "Finite nuclei under extreme conditions of mass, isospin and temperature : a relativistic Hartree-Fock-Bogoliubov description." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112220/document.
Full textAbstract:
La théorie covariance de la fonctionnelle de la densité (CDF), basée sur un petit nombre de paramètres ajustables, a été utilisée avec succès pour décrire l’état fondamental et les états excités des noyaux de la carte nucléaire, pour A>12. Cette approche permet de décrire les systèmes nucléaires finis avec un Lagrangien hadronique universel résolu dans le cadre de l'approche Relativiste-Hartree-Fock-Bologuibov (RHFB). Ce modèle est également utilisé pour l'étude des étoiles compactes, car il peut être étendu à des densités élevées où la relativité restreinte ne peut pas être ignoré. Ce modèle peut également être étendu pour inclure la contribution des hypérons et ainsi que d'autres particules exotiques. Dans ce travail, la description et des prédictions basées sur l'approche RHFB pour les noyaux dans des conditions extrêmes de la masse, d'isospin et de température sont présentés.Dans la première partie de cette thèse, nous explorons l'apparition de nouvelles fermetures de couches sphériques pour des noyaux super-lourds, où les fermetures de couches sont caractérisées en termes de gap à deux nucléons. Les résultats dépendent légèrement des Lagrangians effectifs utilisés, mais les nombres magiques au-delà de ^{208} Pb sont prédit pour un nombre de protons Z=120 et 138, et pour un nombre de neutrons N=172, 184, 228, et 258. Les effets de couche sont sensibles à différents termes de champ de moyen, tels que le couplage spin-orbite, la masse scalaire et la masses effective, ainsi que l'interaction de tensorielle de Lorentz. Ces termes ont des poids différents dans les Lagrangians effectifs employées, expliquant les variations, somme toute petites, dans leurs prédictions. Employant le modèle RHFB le plus avancé, nous avons trouvé que le nucléide ^{304} 120 est favorisée comme étant le prochain noyau sphérique doublement magique au-delà de ^{208} Pb.Dans la deuxième partie de cette thèse, nous étudions l'apparition de nouveaux nombres magiques pour les noyaux de masse intermédiaire riches en neutrons, et nous analysons le rôle des interactions pseudo-vecteur et de tensorielle de Lorentz. Basé sur la transformation de Foldy-Wouthuysen, nous discutons en détail le rôle joué par les différents termes des interactions pseudo-vecteur et de tensorielle de Lorentz. Dans l'apparition des nouveaux nombres magiques N=16 , 32 et 34. Les noyaux ^{24} O ^{48} Si et ^{52,54} Ca sont prédits avec un grand gap au niveau de Fermi et un gap d'appariement zéro (^{24} O,^{54}Ca ) ou quasi-nul (^{48} Si,^{54} Ca), les rendant candidats pour de nouveaux nombres magiques des noyaux riches en neutrons. Nous constatons que les interactions de Lorentz pseudo-vecteur et tensorielle induisent des évolutions très spécifiques des énergies à une particule, ce qui pourrait signer la présence et la nécessité d'approches relativistes avec des interactions d'échanges de mésons.Dans la dernière partie de cette thèse, nous étudions les transitions de phase et excitations thermiques des deux noyaux stables et faiblement liés. Les prédictions de divers Lagrangiens relativistes et des différentes interactions d'appariement sont discutées. La température critique de la transition d'appariement dépend linéairement du gap d'appariement à température nulle, et cette dépendance est similaire pour une interaction de portée nulle ou bien finie. Les calculs présentés montrent des caractéristiques intéressantes des corrélations d'appariement à température finie, comme la persistance d'appariement et les phénomènes de re-entrance superfluide. En outre, nous analysons la réponse thermique de certains noyaux.En conclusion, le travail présenté dans cette thèse montre des résultats très intéressants et nouveaux pour trois des questions les plus importantes en physique nucléaire: la quête d'un nouvel îlot de stabilité dans la région des super-lourds, l'apparition de nouveaux nombres magiques dans les noyaux exotiques, et la réponse d'un système finis aux excitations thermiquesThe covariant density functional (CDF) theory with a few number of parameters has been successfully employed to describe ground-state and excited-states of nuclei over the entire nuclear landscape for A > 12. It describes finite nuclear systems with a universal hadronic Lagrangian, which is solved considering the relativistic-Hartree-Fock-Bologuibov approach (RHFB). This model is also employed for the study of compact stars, since it can be extended to high densities where special relativity cannot be ignore. This model can also be extended to include the contribution of hyperons and as well as other exotic particles. In this work, the description and some predictions based on RHFB approach for nuclei under extreme conditions of mass, isospin and temperature are presented.In the first part, we explore the occurrence of spherical shell closures for superheavy nuclei, where shell closures are characterized in terms of two-nucleon gaps. The results depend slightly on the effective Lagrangians used, but the magic numbers beyond ^{208}Pb are generally predicted to be Z = 120 and 138 for protons, and N = 172, 184, 228, and 258 for neutrons. Shell effects are sensitive to various terms of the mean-field, such as the spin-orbit coupling, the scalar and the effective masses, as well as the Lorentz-tensor interaction. These terms have different weights in the effective Lagrangians employed, explaining the (relatively small) variations in the predictions. Employing the most advanced RHFB model, we founded that the nuclide ^{304}120 is favored as being the next spherical doubly-magic nucleus beyond ^{208}Pb.In the second part, we investigate the formation of new shell gaps in intermediate mass neutron-rich nuclei, and analyze the role of the Lorentz pseudo-vector and tensor interactions. Based on the Foldy-Wouthuysen transformation, we discuss in detail the role played by the different terms of the Lorentz pseudo-vector and tensor interactions in the appearance of the N=16, 32 and 34 shell gaps. The nuclei ^{24}O, ^{48}Si and ^{52,54}Ca are predicted with a large shell gap and zero (^{24}O, ^{52}Ca) or almost zero (^{48}Si, ^{54}Ca) pairing gap, making them candidates for new magic numbers in neutron rich nuclei. We find that the Lorentz pseudo-vector and tensor interactions induce very specific evolutions of single-particle energies, which could clearly sign their presence and reveal the need for relativistic approaches with exchange interactions.In the last part, we study the phase transitions and thermal excitations of both stable and weakly-bound nuclei. The predictions of various relativistic Lagrangians and different pairing interactions are discussed. The critical temperature of the pairing transition is found to depend linearly on the zero-temperature pairing gap, and this dependence is similar for a zero-range or a finite-range pairing interaction. The present calculations show interesting features of the pairing correlations at finite temperature, such as the pairing persistence and pairing re-entrance phenomena. Also, we analyze the thermal response of some nuclei.In conclusion, the work presented in this thesis shown interesting and new results for three of the most important questions in nuclear physics: the quest for a new island of stability in the superheavy region, the appearance of new magic numbers in exotic nuclei, and the response of finite-systems to thermal excitations
31
Nowakowski, Daniel [Verfasser], Michael Akademischer Betreuer] Buballa, and Jochen [Akademischer Betreuer] [Wambach. "Inhomogeneous chiral symmetry breaking in isospin-asymmetric strong-interaction matter / Daniel Nowakowski ; Michael Buballa, Jochen Wambach." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2017. http://nbn-resolving.de/urn:nbn:de:tuda-tuprints-61570.
Full text
32
Knothe, Angelika Hildegard. "Quantum Hall Ferromagnetism in Multicomponent Systems." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS595/document.
Full textAbstract:
Cette thèse traite des systèmes de Hall quantiques en deux dimensions, dans lesquels les électrons peuvent porter plusieurs degrés de liberté discrets différents. Le ferromagnétisme de Hall quantique fournit une manière de traiter ces degrés de liberté électroniques comme des spins et isospins effectifs des électrons. Les différentes phases du système correspondent alors à différents ordres de spin ou d'isospin. En exploitant cette analogie, nous explorons différents aspects des systèmes bi-dimensionnels dans le régime de Hall quantique en étudiant la structure correspondante des spins et isospins. Ce travail consiste en trois parties qui analysent différents matériaux bi-dimensionnels dans le régime de l'effet Hall quantique. Dans chaque projet, nous utilisons la théorie de Hartree-Fock pour étudier le système à plusieurs composantes de spin et d'isospin dans l'approximation de champ moyen. Toutes nos considérations sont directement stimulées par des résultats expérimentaux. Notre motivation principale est d'obtenir une compréhension plus profonde des processus physiques et des mécanismes qui déterminent les propriétés des matériaux à partir d'investigations exclusivement théoriques de modèles abstraits. Nous espérons que cela permettra par la suite de tirer des conclusions sur les expériences, de donner des explications aux phénomènes observés ainsi que de donner des perspectives pour des investigations futuresThe present thesis deals with two-dimensional quantum Hall systems in which the electrons may be endowed with multiple discrete degrees of freedom. Quantum Hall ferromagnetism provides a framework to treat these electronic degrees of freedom as effective spins and isospins of the electrons. Different orderings of the electronic spins and isospins then characterise different possible phases of the system. Using this analogy, various aspects of the two-dimensional systems in the quantum Hall regime are explored theoretically by studying the corresponding spin and isospin structure. The work consists of three parts in which different two-dimensional materials are investigated in the quantum Hall regime. In any of the three projects presented within this thesis, Hartree Fock theory is employed to study the multicomponent spin and isospin system at the mean field level. All our considerations are stimulated directly by experimental results. We draw our main motivation from the key idea that purely theoretical investigations of abstract models may us allow to obtain deeper insights into the physical processes and mechanisms that determine the properties of the materials. This, in turn, we hope to allow conclusions about the experiments by providing possible explanations of the phenomena observed, as well as prospects for future investigations
33
Prados, Estevez F. M. "Isospin purity of T=1 states in the A=38 nuclei via lifetime measurements in 38 K." Thesis, University of Brighton, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426974.
Full textAbstract:
with T2DM have more difficulty in losing weight than people without T2DM when following Lifestyle intervention. In patients who were unable to lose weight following Lifestyle intervention alone, the addition of Sibutramine to Lifestyle advice enabled similar or greater amounts of weight 1m"> as pair matched patients who successfully lost weight in the Lifestyle clinic. These studies demonstrate that effective dietetic management for patients with T2DM result in positive outcomes, such as weight loss. However, changes to standard care would be required towards more intensive and longer term dietetic interventions as well as the use of pharmacotherapy. The treatment of obesity in T2DM needs to be more aggressive to enable people to manage their weight, and different weight loss strategies should be attempted until success prevails. Dietitians provide an excellent foundation on which new skills for obesity management can be built, which then urgently need to be implemented nationwide to help turn the tide on the obesity epidemic.
34
Albuquerque, Luciana Patrícia Martins Nunes Pereira. "Análise acústica das vogais orais de isosos no português europeu." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/11436.
Full textAbstract:
Mestrado em Ciências da Fala e da AudiçãoEnquadramento: Com o decorrer dos anos, fruto das alterações verificadas nas estruturas que participam na produção de fala, a qualidade vocal do indivíduo altera-se, com impacto ao nível dos parâmetros acústicos. Objetivo: Este estudo tem como objetivo determinar a influência da idade, do género e do tipo de vogal na variação dos parâmetros acústicos (frequência fundamental (F0), primeiro formante (F1), segundo formante (F2) e duração) das vogais orais produzidas por idosos falantes do Português Europeu (PE). Método: Os dados utilizados foram recolhidos pela Microsoft Language Development Center (MLDC) através da campanha “Doar a Voz”. Da amostra selecionada fazem parte 78 informantes com idades compreendidas entre os 60 e os 90 anos, divididos em seis grupos de acordo com o género e a faixa etária. Foram analisadas todas as vogais em posição tónica e contexto de oclusivas e fricativas. As palavras que continham as vogais alvo foram anotadas manualmente no Praat e os parâmetros em análise foram extraídos de forma semiautomática. Resultados: Em relação à idade, verificou-se que a duração é o único parâmetro que varia de forma significativa com o aumento dos anos, sendo os seus valores superiores nos indivíduos de [81-90] anos. No que concerne ao género, todos os parâmetros, exceto a duração, revelaram diferenças estatisticamente significativas, sendo os valores de F0, F1 e F2 superiores no género feminino. Os parâmetros acústicos também variam significativamente em função da vogal, permitindo distingui-las entre si. O F1 e o F2 são os que melhor permitem essa diferenciação. Quando comparados os resultados obtidos para os idosos com os referidos na literatura para os adultos do PE, observou-se que a F0 diminuiu no género feminino e aumentou no género masculino, com o envelhecimento. Quanto ao F1, observou-se um aumento generalizado nos idosos de ambos os géneros. Por outro lado, F2 aumentou nas vogais posteriores e diminuiu nas vogais anteriores. Em relação à duração, esta foi inferior nos idosos comparativamente aos adultos. Conclusão: Os resultados obtidos neste estudo evidenciam que os parâmetros F0, F1, F2 e duração variam com o envelhecimento. No entanto, o impacto da idade é diferente em cada parâmetro.
Background: With aging the vocal quality of the speaker changes due to speech production structural changes affecting the acoustic parameters. Objective: The goal of this study is to determine the influence of age, gender and type of vowel in the acoustic parameters (fundamental frequency (F0), first formant (F1), second formant (F2) and duration) of the vowels produced by elderly speakers of European Portuguese. Method: The data used was obtained by Microsoft Language Development Center (MLDC) through “Doar a Voz” campaign. The selected sample is composed by 78 speakers between 60 and 90 years old, the sample was divided into six groups according to their gender and age. All the vowels in stressed position and in plosive and fricative context were analysed. The words with target vowels were manually annotated in Praat and the parameters under analysis were semi-automatically extracted. Results: Regarding the age, it was observed that duration is the only parameter that significantly changes with aging, the higher value was obtained for the age of [81-90]. Concerning the gender, all the parameters, except duration, present statistically significant differences, the maximum values for F0, F1 and F2 was observed in females. Moreover, the acoustic parameters also change significantly with the vowel, allowing to distinguish between them. F1 and F2 are those which best allow this differentiation. Comparing the results obtained with the ones referred in the literature for adult speakers of European Portuguese, F0 reduces for females and increases for males with aging. On the one hand, it was verified that F1 generally increases with aging. On the other hand, F2 only increases for back vowels, whereas, for front vowels, F2 decreases with aging. The comparison also reveals that duration is lower for elderly speaker than for adult speakers. Conclusion: The results of this study show that the parameters F0, F1, F2 and duration change with aging. However, the impact of the age is different in each parameter.
35
Diel, Felix [Verfasser], Jan [Gutachter] Jolie, and Andreas [Gutachter] Zilges. "Spin-Isospin Structure Investigation via στ-type Transitions starting from 64Zn / Felix Diel ; Gutachter: Jan Jolie, Andreas Zilges." Köln : Universitäts- und Stadtbibliothek Köln, 2019. http://d-nb.info/1198399139/34.
Full text
36
Milne, Scott Alexander. "Investigation of isospin symmetry breaking in the f7/2 region, studied through one-nucleon knockout and lifetime measurements." Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/16793/.
Full textAbstract:
In this thesis, the results of two experiments are presented. The first experiment was performed at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU), USA, while the second experiment was performed at the Gesellschaft für SchwerIonenforschung (GSI) facility near Darmstadt, Germany. For the experiment performed at MSU, γ-ray spectroscopy has been performed for both the mirror Tz=±3/2 pair 53Ni and 53Mn, produced via mirrored one-nucleon knockout, and the Tz=-1 nuclide 52Co, produced via one-neutron knockout. Several new transitions have been identified in both 53Ni and 52Co, from which new level schemes have been constructed. The presence of a high-spin isomeric state (Jπ=19/2-) in the 53Co beam facilitated the study of high-spin states up to and including the 11+ band termination state in 52Co, where this work also represents the first use of this new technique (isomer knockout) to study high-spin states in exotic nuclei. Relative cross sections for knockout have been analysed and compared with reaction model calculations, where a high level of agreement is observed, especially for states in 52Co. Mirror Energy Differences (MED) between Isobaric Analogue States (IAS) have been measured, compared to large scale shell-model calculations and interpreted in terms of INC effects for both the Tz=±1, A=52 and Tz=±3/2, A=53 mirror pairs. The analysis presented here demonstrates the importance of including a full set of J-dependent INC terms to explain the experimental observations. Finally, lifetimes for the long-lived Jπ=5/2- analogue states in both 53Mn and 53Ni have been extracted through lineshape analysis, giving half-lives of T1/2=120(14)ps and T1/2=198(12)ps, respectively. In the experiment performed at GSI, Coulex and lifetime measurements (using a novel 'stretched gold target' technique) were performed for the analogue 2+(T=1) → 0+(T=1) transition across the A=46, T=1 isobaric triplet 46Cr(Tz=-1), 46V(Tz=0) and 46Ti(Tz=+1). Preliminary Coulex cross sections have been obtained and a 'proof-of-principle' test has been performed for the new lifetime method.
37
Johnsson, Fellbo Annika, and Linnea Svensson. "Fetma föder fetma - en enkätstudie om utökade interventioner inom basprogrammet i mödra- och barnhälsovård ger effekt på barnens viktutveckling." Thesis, Linnéuniversitetet, Institutionen för hälso- och vårdvetenskap, HV, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-19493.
Full textAbstract:
Bakgrund: Övervikt och fetma är ett ökande problem i Sverige och stora delar av världen, för både vuxna och barn. Övervikt och fetma hos modern innan och under graviditeten ökar risken för övervikt och fetma hos barnet. Risken för fetma hos barn ökar i proportion med föräldrarnas fetma. Fetma vid 4 års ålder ökar riskerna för fetma senare i livet. Ett överviktigt/obest barn har generellt sämre livskvalité och är oftare deprimerade, fetma orsakar också sjukdomar som t.ex. högt blodtryck och diabetes. Att amma sitt barn främjar dess aptitreglering och förebygger övervikt. Syfte: Syftet med denna studie var att undersöka om utökade interventioner inom ramen för ordinarie basprogram under graviditet och småbarnstid hos kvinnor med BMI över 25 påverkade viktutveckling/ISOBMI och amningslängd hos barnet fram till fyra års ålder. Metod: Interventionsstudie omfattande 182 barn indelade i en interventionsgrupp (94) och en jämförelsegrupp (88). Enkäter rörande barnets vikt, längd och matvanor samlades in och analyserades när barnet var 10 månader, 2,5 år och 4 år gammalt Resultat: En signifikant skillnad sågs mellan grupperna vid fyra års ålder, då fler var överviktiga och feta i jämförelsegruppen. Medelvikten skilde ett kg. En trend sågs i alla viktkategorier där jämförelsegruppen vägde mer än interventionsgruppen. Det sågs ingen signifikant skillnad i amningslängd mellan grupperna.Slutsats: Överviktiga/feta kvinnor får i större utsträckning överviktiga/feta barn. Vår studie visar att små interventioner gör skillnad.Background: Obesity is an increasing problem in Sweden and large parts of the world, for both adults and children. Overweight and obesity in the mother before and during pregnancy increases the risk of overweight and obesity in the child. The risk of childhood obesity is increasing in proportion with parental obesity. Obesity at age four increases the risk of obesity later in life. An overweight / obese child generally have worse quality of life and are more often depressed, obesity also causes diseases such as hypertension, and diabetes. To breastfeed the child promotes its appetite control and prevents obesity. Purpose: The purpose of this study was to investigate whether enhanced interventions within the framework of regular base program during pregnancy and under the children’s first four years in women with a BMI over 25 affects weight gain / ISOBMI and lactation length. Method: The intervention study of 182children divided into an intervention group (94) and a comparison group (88). Surveys regarding the child's weight, height and dietary habits were collected and analyzed when the child was 10 months, 2.5 years and 4 years old Results: A significant difference was seen between the groups at age four, when more were overweight and obese in the comparison group. The average weight differed one kg. A trend was seen in all weight categories in which the control group weighed more than the intervention group. There was no significant difference in breastfeeding duration between the groups. Conclusion: Overweight / obese women have a greater degree of overweight / obese children. Our study shows that small interventions make a difference.
38
Li, Calzi Melinda Jasmine Sirio. "Fattibilità della misura di cattura neutronica sugli isotopi dispari del gadolinio." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10474/.
Full textAbstract:
In questo lavoro di tesi ci proponiamo di determinare lo spessore degli isotopi ^157Gd e ^155Gd in vista della misura della sezione d’urto di cattura neutronica presso la facility n_TOF del CERN. La principale motivazione dell’esperimento è legata alla necessità di ottenere misure più accurate per le applicazioni ai reattori nucleari. Inoltre, i nuovi risultati, potranno essere sfruttati anche per applicazioni ai recenti sviluppi nella Terapia di Cattura Neutronica e per costruire nuovi rivelatori nell’ambito della ricerca del neutrino.
La misura sarà effettuata nella prima area sperimentale EAR-1 di n_TOF, equipaggiata con rivelatori, come per esempio gli scintillatori liquidi al benzene deuterato (C6 D6) particolarmente adatti per questi tipi di misura.
La sezione d’urto di questi due isotopi cambia di molti ordini di grandezza al variare dell’energia dei neutroni incidenti. Per questo motivo, lo studio effettuato in questa tesi ha mostrato che sono necessari due campioni altamente arricchiti per ogni isotopo da misurare: un campione estremamente sottile per energie del neutrone fino a 100 meV,
e uno più spesso per energie maggiori. Inoltre per questi campioni sono stati determinati le densità areali necessarie per lo svolgimento dell’esperimento affinchè avvenga il fenomeno di trasmissione dei neutroni.
39
Astier, Alain. "Recherche expérimentale de noyaux exotiques en isospin et en spin à l'aide de guides d'ions et de multidétecteurs γ." Lyon 1, 1992. http://www.theses.fr/1992LYO10067.
Full textAbstract:
Ce travail de these est relatif a l'etude de la structure nucleaire de noyaux exotiques en isospin et en spin par deux approches complementaires: radioactivite en ligne et reactions de fusion-evaporation. La premiere partie decrit la mise au point d'un guide d'ions couple au separateur en ligne aupres de l'accelerateur sara a grenoble. Ce dispositif permet l'etude de noyaux d'elements tres refractaires et de courtes durees de vie (jusqu'a 1 ms). La reaction #2#3#8u( 40 mev, f) produisant des radioisotopes tres riches en neutrons, toutes les chaines de a=96 a 122 ont ete etudiees par spectroscopie conventionnelle. Plus de 60 taux de production (de 10 a 1850 at/c#p#a#r#t) ont ete mesures, la frontiere des noyaux riches en neutrons connus atteinte, comme #1#1#7rh(440 ms) et plusieurs activites inconnues ont ete detectees dans les series isobariques a=113-118. Sept nouveaux isotopes ont ete decouverts en finlande avec un guide d'ions similaire et un faisceau de protons de 20 mev. La comparaison des rendements de la fission induite par et par protons montre la predominance de la fission symetrique autour de a=115 pour un faisceau d'. La seconde partie de ce travail est relative aux structures des etats de hauts spins observes dans la region de masse a=190 avec differents multidetecteurs , le chateau de cristal a strasbourg et tessa3 a daresbury. Le chateau de cristal a permis de connaitre les niveaux de #1#9#3pb jusqu'a pres de 5 mev d'energie d'excitation et plus de 20 h de moment angulaire. Avec tessa3 en grande-bretagne a ete observee dans #1#9#8pb la premiere bande collective rotationnelle dipolaire i=1 de la region a=190, interpretee avec une tete de bande a haut k de forme aplatie
40
Bonnet, Jan [Verfasser]. "Effects of isospin symmetry breaking in light mesons and application to the anomalous magnetic moment of the muon / Jan Bonnet." Gießen : Universitätsbibliothek, 2018. http://d-nb.info/1161670378/34.
Full text
41
Voutier, Eric. "Approche semiclassique de la self-énergie du delta dans un noyau : application au problème des fonctions réponses de spin-isospin." Lyon 1, 1989. http://www.theses.fr/1989LYO10168.
Full textAbstract:
La self-energie du delta est un element important de la comprehension d'un grand nombre de reactions (pion-noyau, photon-noyau, echange de charges. . . ) dans la region de la resonance. La self-energie n'est pas une observable mais l'interpretation des reactions d'absorption de pions (par exemple) met en evidence l'existence de phenomenes lies a la desexcitation du delta
42
Adlarson, Patrik. "Studies of the Decay η→π+π-π0 with WASA-at-COSY." Doctoral thesis, Uppsala universitet, Kärnfysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-181236.
Full textAbstract:
In 2008 a large statistics sample of approximately 1·107 η-decays has been collected with the WASA detector at COSY using the pd→3Heη reaction at the beam kinetic energy of 1 GeV. These data are being used to study the not so rare η decays involving charged pions, like η→π+π-π0. This decay proceeds mainly via a strong isospin violating contribution, where the decay width is proportional to the light quark mass difference squared, (md-mu)2. In addition this decay can be used to search for C-violating effects. The analysis is presented and the Dalitz plot parameters with statistical and systematical uncertainties are determined from a sample of 1.33·105 η→π+π-π0 events in the Dalitz plot. The asymmetry parameters with statistical uncertainties are presented which show no evidence of C-violation.WASA-at-COSY
43
Taylor, Paul Andrew. "Nuclear Binding Energy in Terms of a Redefined (A)symmetry Energy." Thesis, Boston College, 2004. http://hdl.handle.net/2345/460.
Full textAbstract:
Thesis advisor: Kevin S. BedellWe investigate the structure of the equation of state of finite nuclear matter by examining the nature of isospin dependence in the (a)symmetry energy term. In particular, we include in the description of the binding energy fourth-order dependence with respect to the asymmetry factor, (N-Z)/A, and the regime of the l=0 Landau parameter, F0´ , is required to be less than –1. This modified equation predicts a minimum binding energy where N≠Z, in addition to the standard symmetric minimum when N=Z. Results with the new asymmetry energy term are compared with experimental binding and symmetry energies from standard semi-empirical mass formulas. Importantly, this method reveals one possible mechanism for producing the phenomenon of neutron excess which is seen in physical nuclei
Thesis (BS) — Boston College, 2004
Submitted to: Boston College. College of Arts and Sciences
Discipline: Physics
Discipline: College Honors Program
44
Brown, James. "Gamma-ray Spectroscopy of Tz+ 3/2 Mirror Nuclei in the F7/2 Shell : Isospin Breaking Effects at large Proton Excess." Thesis, University of York, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516698.
Full text
45
Mustonen, E. M. (Eva-Maria). "Ihmisen iloksi ja hyödyksi:laukka- ja metsästyshevosten valitseminen ja jalostus 1700-luvun Isossa-Britanniassa." Master's thesis, University of Oulu, 2014. http://urn.fi/URN:NBN:fi:oulu-201404031236.
Full textAbstract:
Laukka- ja metsästyshevosista on vuosisatojen aikana tullut osa brittiläistä kulttuuria. Brittien vaurastuminen mahdollisti näiden uudentyyppisten hevosten jalostamisen 1700-luvulla. Tuolloin Ison-Britannian ylä- ja keskiluokka ryhtyi jalostamaan hevosia laukka- ja metsästysurheiluun. Laukkakilpailujen ja ketunmetsästyksen suosio johti harrastehevosten jalostamiseen ja englannin täysiverisen kehittymiseen hevosrotuna. Ison-Britannian hevoskannan parantamiseen käytettiin tässä vaiheessa paljon Lähi-idästä ja Pohjois-Afrikasta tuotuja hevosia.
Tässä Pro gradussa tarkasteltiin, kuinka britit käytännössä jalostivat laukka- ja metsästyshevosia 1700-luvulla, ja miksi näitä hevosia kasvatettiin ja hoidettiin juuri tietyllä tavalla. Tutkimuksen aineistona käytettiin kahtakymmentä 1700-luvun Isossa-Britanniassa julkaistua hevosenhoito-opasta. Hevosenhoito-oppaista tutkittiin niitä ohjeita, joita oppaiden kirjoittajat antoivat laukka- ja metsästyshevosista, etenkin siitoshevosten valitsemisesta ja hoitamisesta.
Tutkimus kuului humanistisen eläintutkimuksen piiriin, ja se oli luonteeltaan teoreettinen ja laadullinen. Tunnetuimpia lähdeteoksia olivat Gervase Markhamin, Jaqcues de Solleyselin, William Cavedishin ja William Osmerin hevosenhoito-oppaat. Tutkimustulokset tarjoavat arvokasta lisätietoa hevosjalostuksesta ja brittiläisten hevosten kehityksestä 1700-luvulla.
Tutkimuksessa selvisi, että britit jalostivat laukka- ja metsästyshevosia tietoisesti ja valikoiden jo 1700-luvulla. Britit halusivat laukka- ja metsästyshevostensa olevan kauniita ja terveitä, joten jalostustoiminta tähtäsi näiden ominaisuuksien saavuttamiseen. Hevosoppaiden kirjoittajat olivat tietoisia siitä, että tietyt piirteet periytyvät vanhemmilta jälkeläisille. Tammojen ternimaidon saannin rajoittaminen pikkuvarsoilta saattoi vaikuttaa siihen, että Isossa-Britanniassa kasvatetuilla hevosilla oli heikko vastustuskyky. Hevosoppaiden kirjoittajat pitivät hevosten huolellista kouluttamista tärkeänä kautta vuosisadan.
Tutkimus osoitti, että hevoset nähtiin 1700-luvulla tuntevina ja jopa ajattelevina yksilöinä, jotka kehittyivät omaan tahtiinsa. Valistuksen aatteet vaikuttivat selvästi eläinkäsitykseen. Hevosoppaiden kirjoittajat myös tuomitsivat väkivallan eläimiä kohtaan. 1700-luvulla laukka- ja metsästyshevoset olivat ihmisten palvelijoita ja arvokasta omaisuutta. Hevosta pidettiin sekä jalona luontokappaleena että ihmisen uskollisena kumppanina, josta saatiin jalostamisen avulla yhä parempi.
46
Wendt, Andreas [Verfasser]. "Isospin symmetry in the sd shell: Coulomb excitation of 33Ar at relativistic energies and the new 'Lund-York-Cologne-Calorimeter' / Andreas Wendt." München : Verlag Dr. Hut, 2013. http://d-nb.info/103184497X/34.
Full text
47
Kunovič, Barbara. "Izosukinio formalizmas jj ryšyje." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20070816_171044-64947.
Full textAbstract:
Buvo parodyta, kaip gali būti naudojama JAHN programa darbui su atominėmis ir branduolinėmis būsenos funkcijomis izosukinio bazėje. Visa informacija apie atomines ar konfigūracines būsenos funkcijas gali būti pateikta įprastame formate. Tokia tvarka leistų greitą priėjimą prie reikiamų duomenų ir paprastą komandų valdymą. Būsenos funkcijų klasifikacijas izosukinio bazėje, viendalelius kilminius koeficientus CFP, dvidalelius kilminius koeficientus CFGP, transformacijos matricas iš LS ryšio į izosukinio ryšio bazę galima surasti naudojant atitinkamas komandas, kurių sintaksė yra analogiška literatūroje naudojamiems žymėjimams. Trumpas ir efektyvus sluoksnių ir konfigūracinių būsenų įvedimas daro programą atsparesnę klaidoms ir leidžia vartotojui sukurti atskiras koeficientų lenteles tam tikriems sluoksnių būsenų termams izosukinio bazėje. Tokios lentelės gaunamos vienos komandinės eilutės pagalba. Tikimasi, kad JAHN programa padės smulkiau analizuoti įvairių fizikinių operatorių matricinius elementus izosukinio bazėje. Komandos jj ryšiui, analogiškai kaip ir LS ryšiui, yra pateikiamos kuo mažiau nutolstant nuo jų užrašymo formos knygose ar straipsniuose. Įvedant nesudėtingas komandas nustatome sluoksnio charakteristikas. CFGP reikšmės irgi randamos JAHN programa, kas gerokai sutaupo laiko, kadangi jų nereikia ieškoti spausdinamose lentelėse.We have shown how JAHN has been used for dealing with atomic or nuclear state functions within an isospin basis. All information about the atomic or the configuration state functions can be stored in a suitable format in order to allow a fast access and manipulation. Apart from the classification of the shell states in an isospin basis the coefficients of fractional parentage, the coefficients of fractional grandparentage, the transformation matrices for going from LS – coupled to an isospin – coupled basis can be calculated interactively. A short and powerful notation has been introduced for the shell and configuration states which makes the program less prone to errors and which enables the user to create an electronic table of shell state terms or CFP in isospin basis within only a single command line. The JAHN program will support a more detailed analysis of the matrix elements of various physical operators by using an isospin basis. The algorithms for jj coupling is analogous with LS coupling and they are presented in the way, which is commonly used in printed books and articles. We define layer characteristics from ordinary commands. CFGP values are also calculated with JAHN program, which is very convenient for saving the time that is needed to look up for those values in the printed tables.
48
Prévost, Aurélien. "Recherche de grandes déformations nucléaires dans des noyaux exotiques en spin et en isospin à l'aide des multidétecteurs gamma EUROBALL IV et EXOGAM." Phd thesis, Université Claude Bernard - Lyon I, 2003. http://tel.archives-ouvertes.fr/tel-00003114.
Full textAbstract:
Ce travail de thèse est dédié à l'étude des noyaux lourds soumis à des conditions extrêmes de spin et d'isospin. Les expériences présentées ont été menées à l'IReS de Strasbourg et au GANIL de Caen avec les multidétecteurs gamma EUROBALL IV et EXOGAM auprès, respectivement, des accélérateurs VIVITRON et SPIRAL. Les noyaux étudiés ont été peuplés via des réactions de fusion-évaporation. Pour exploiter les données, nous avons développé de nouvelles méthodes d'analyse reposant sur la logique floue. Deux expériences ont été réalisées auprès d'EUROBALL IV et portaient sur les noyaux superdéformés de masse A~190-200 à savoir les isotopes superdéformés de plomb 197,l98Pb et l'isotope superdéformé de bismuth 196Bi. Dans le premier cas, nous avons découvert six nouvelles bandes superdéformées ce qui nous a permis de mettre en évidence un couplage entre vibrations octupolaires et excitations intrinsèques. Dans le second, nous avons observé la transition superdéformée gamma de plus basse énergie si on exclut les isomères de fission. Ces résultats ont été interprétés à partir de calculs théoriques microscopiques auto-cohérents statiques et dynamiques effectués en collaboration avec des physiciens des groupes de Physique Théorique de l'IPN Lyon et du SPTh/Saclay.
La dernière partie de ce travail a concerné la recherche de grandes déformations dans les noyaux de terres-rares de la zone de masse A~120-130 très déficients en neutrons situés près de la ligne d'émission spontanée de proton. Cette étude a été mise en oeuvre avec le multidétecteur gamma EXOGAM en couplage avec le détecteur de particules chargées légères DIAMANT et le faisceau radioactif de 76Kr délivré par SPIRAL.
49
Prévost, Aurélien. "Recherche de grandes déformations nucléaires dans des noyaux exotiques en spin et en isospin à l'aide des multidétecteurs γ EUROBALL IV et EXOGAM." Lyon 1, 2003. http://tel.archives-ouvertes.fr/docs/00/04/54/64/PDF/tel-00003114.pdf.
Full textAbstract:
Ce travail de thèse est dédié à l'étude des noyaux lourds soumis à des conditions extrêmes de spin et d'isospin. Les expériences présentées ont été menées à l'IReS de Strasbourg et au GANIL de Caen avec les multidétecteurs γ EUROBALL IV et EXOGAM auprès, respectivement, des accélérateurs VIVITRON et SPIRAL. Les noyaux étudiés ont été peuplés via des réactions de fusion-évaporation. Pour exploiter pleinement les dónnées, nous avons développé de nouvelles méthodes d'analyse reposant sur la logique floue. Deux expériences ont été réalisées auprés d'EUROBALL IV et portaient sur les noyaux superdéformés de masse A~190-200 à savoir les isotopes superdéformés de plomb 197,198 Pb et l'isotope de bismuth 196Bi. Dans le premier cas, nous avons découvert six nouvelles bandes superdéformées ce qui nous a permis de mettre en évidence un couplage entre vibrations octupolaires et excitations intrinsèques. Dans le second cas, nous avons observé la transition superdéformée γ de plus basse énergie si on exclut les isomères de fission. Ces résultats ont été interprétés à partir de calculs théoriques microscopiques auto-cohérents statiques et dynamiques effectués en collaboration avec des physiciens de groupe de Physique Théorique de l'IPN Lyon et du SPTh/Sacllay. La dernière partie de ce travail a concerné la recherche de grandes déformations dans des noyaux de terres-rares de la zone de masse A~120-130 très déficients en neutrons situés près de la ligne d'émission spontanée de proton. Cette étude a été mise en oeuvre avec le mutlidétecteur γ EXOGAM en couplage avec le détecteur de particules chargées légères DIAMANT et le faisceau radioactif de 76Kr délivré par SPIRAL.
50
Guy, Alexandre. "Synthèse biomimétique de la 15-F2t-IsoP. Synthèse de l'ent 5,6-dihydro-2,3-dinor-15-F2t-IsoP." Montpellier 2, 1998. http://www.theses.fr/1998MON20183.
Full textAbstract:
Les isoprostanes (isops), isomeres des prostaglandines, sont une nouvelle classe de produits naturels decouvertes dans les annees 1990. Les isops sont naturellement formees, lors de l'attaque oxydante de l'acide arachidonique (aa), par reaction de cyclisation radicalaire intramoleculaire avec introduction de trois atomes d'oxygene. La 15-f#2#t-isop, la plus abondante, possede de puissantes activites biologiques et est actuellement consideree comme un bon marqueur de la peroxydation lipidique. A cause de l'interet porte a ce compose, nous en avons developpe la synthese totale. La strategie retenue est une strategie biomimetique. En effet, l'etape cle de cette synthese utilise le mecanisme suppose de la formation in vivo des isops au moyen d'une cyclisation radicalaire de type 1,5,7-octadienyle d'un motif a 20 atomes de carbone mimant l'aa. La synthese biomimetique de la 15-f#2#t-isop a permis de confirmer la biosynthese des isops et sa formation possible a partir de l'aa esterifie. Nous avons aussi aborde la synthese de l'enantiomere d'un des metabolites urinaires de la 15-f#2#t-isop, l'ent-15(rs)-5,6-dihydro-2,3-dinor-15-f#2#t-isop. L'approche retrosynthetique est basee sur la formation d'un cycle pentanique polysubstitue de configuration adequate sur lequel sont fixes les chaines laterales du metabolite. L'obtention de ces deux molecules, en particulier la 15-f#2#t-isop, pouvant etre marquee au deuterium ou au tritium, presente un interet majeur pour des etudes biologiques. D'autre part, ces deux isops peuvent etre un index de peroxydation lipidique representatif des attaques oxydantes in vivo.