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Dissertations / Theses on the topic 'Nucleons'

Author: Grafiati

Published: 4 June 2021

Last updated: 25 May 2024

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1

Hewson, Paul Joseph. "Chiral symmetry in nucleons." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/chiral-symmetry-in-nucleons(bc2c5e94-1830-465e-b10c-5b7c162e7381).html.

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Chiral perturbation theory allows us to probe the low energy properties of hadrons. In this thesis we have looked at the axial coupling constant (see chapter 4) and baryon number violation (see chapter 5).We calculated the axial coupling constant up to O(p^4) using the extended on mass shell renormalisation scheme in chiral perturbation theory. We also included the decuplet as an explicit degree of freedom. To fit the free parameters in our expression we used a combination of lattice and experimental data. We found that the fourth order corrections were quite large, and we struggled to produce an acceptable fit to the data. We also saw that the running of g_{A}^{pn} with M_\pi predicted by lattice QCD and ChPT at O(p^4) do not agree well. This is likely due to a combination of finite size effects impacting the low pion mass lattice data and the chiral perturbative series converging slowly. For our work on baryon number violation we looked at determining the values of two low-energy constants that appear in the baryon violating chiral Lagrangian. To do this, we matched our expression to lattice data. Previous determinations of the parameters had been done without calculating the effect of loops, ours was the first investigation to see what impact the loop diagrams would have. We found that our determinations of the parameters were in agreement with previous results, suggesting the effect of the loops is small. We also performed a chiral extrapolation, and found that our results were in agreement with previous results that did not account for loop corrections. This suggests that the impact of higher-order corrections is not significant for this baryon-number-violating process.

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2

Al, Mamun Md Abdullah. "Nuclei, Nucleons and Quarks in Astrophysical Phenomena." Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1563991151449461.

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3

FLORE, CARLO. "ACCESSING THE 3D STRUCTURE OF NUCLEONS THROUGH TMD PHENOMENOLOGY." Doctoral thesis, Università degli Studi di Cagliari, 2020. http://hdl.handle.net/11584/284137.

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The three-dimensional structure of nucleons and transverse polarisation phenomena at high energy are subjects of very intensive researches. While collinear QCD at leading twist is not able to describe such kind of events, more extended approaches including intrinsic transverse momentum effects have turned out to be more suitable in this context. In this thesis, phenomenological studies on transverse momentum dependent (TMD) functions are presented. By adopting a TMD approach, we enlight the current knowledge on some of the leading twist polarised TMD functions, such as the (quark and gluon) Sivers distributions, the transversity and the Collins functions. The role of the underlying choices in phenomenological analyses, together with the assessment of TMD signals in the data, is particularly emphasised. Indeed, some of the assumptions made on the phenomenological model can influence the outcome of an analysis. In the case of the quark Sivers function, suitable choices on the set of parameters result in a more accurate uncertainty evaluation, while for the TMD transversity relaxing some initial hypothesis eases the tension between phenomenology and lattice QCD estimates of the isovector tensor charge. The poorly known gluon Sivers function (GSF) are also analysed, both in the framework of the Generalised Parton Model (GPM) and its colour gauge invariant extension (CGI-GPM), where two independent GSFs are defined. A first constraint on the size and the sign of these functions, as well as a new GPM extraction, are showed. The extracted TMDs are also adopted to study the single-spin asymmetries observed in polarised proton-proton and lepton-proton processes. The latter reaction is analysed, highlighting the role of the quasireal photon exchange in the unpolarised cross sections and in the asymmetries. Theoretical predictions compared against existing data show a very good description of the measured asymmetries. By means of the estimated gluon Sivers functions, single-spin asymmetries for inclusive J/ψ and photon production in polarised proton-proton reactions are also estimated. At the moment, no clear discrimination between the GPM and the CGI-GPM is possible. A novel Horizon 2020 project, aiming to create an online platform for hadronic and nuclear physics is also presented. In future, it would represent a valuable tool,% in these contexts, and its potential extension to TMD physics could become beneficial also for the TMD community. New data from colliders and fixed target experiments will come in the future. In the quest for understanding polarisation phenomena, a more agnostic, transparent and thorough approach in phenomenological analyses would help in preparing the TMD community to be ready for the next generation of experiments.

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4

Krüger, Andreas. "Effective hamiltonians from field theory for one and two nucleons." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=961473347.

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5

Bosveld, Geert Derk. "Semi-inclusive deep inelastic lepton scattering on nucleons and nuclei." [S.l. : [Groningen] : s.n.] ; [University Library Groningen], 1995. http://irs.ub.rug.nl/ppn/150652445.

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6

Motimele, Kanting Evidence. "A relativistic analysis of proton-induced knockout reactions from oxygen isotopes with direct and inverse kinematics." University of the Western Cape, 2020. http://hdl.handle.net/11394/8187.

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>Magister Scientiae - MSc
In this study a complete set of exclusive (~p; 2p) polarization transfer observables of closed-shell oxygen isotopes are calculated using both direct and inverse kinematics using the relativistic plane wave impulse approximation. The interaction matrix is written in terms of the SPVAT (scalar, pseudoscalar, vector axial vector, tensor) covariants where each amplitude is obtained directly from experimental phase shifts. A relativistic mean eld theory approximation is used to compute boundstate wave functions of the nucleons. We study the evolution of polarization transfer observables within oxygen isotopes and identify observables which may discriminate between these isotopes. The same kinematical conditions are considered for both direct and inverse kinematics: the incident energy is set at 504 MeV and coplanar angles are xed at (22:12 ;􀀀40:30 ). The results indicate that only three spin observables, namely, Ay, P and Dnn distinguish di erent oxygen isotopes at these kinematical conditions in the inverse kinematics.

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7

MERABET, HOUARI. "Production inelastique du charmonium par diffusion de leptons sur des nucleons (noyaux)." Paris 7, 1995. http://www.theses.fr/1995PA077140.

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Une revue detaillee de tous les problemes theoriques lies a la leptoproduction du charmonium a ete faite. Des solutions a ces problemes ont ete proposees. Nous avons presente pour la premiere fois une expression coherente et totalement differentielle de la section efficace. Une etude sur l'influence du mouvement de fermi sur la fonction de distribution des gluons et les consequences qu'aura ceci sur la leptoproduction du charmonium a ete abordee. La possibilite experimentale d'observer ces modifications a ete discutee. Le probleme du facteur de normalisation associe a la leptoproduction du charmonium a ete examine de pres. Nous avons fait une revue critique sur les differentes approximations faites habituellement pour decrire l'amplitude de production ou d'annihilation du charmonium. Nos resultats montrent que ces approximations ne sont pas justifiees. Ils permettent aussi d'ameliorer de facon tres sensible la description theorique de ces processus. La largeur leptonique et la section efficace inelastique ainsi calculees montrent une tres faible dependance par rapport au type de fonction d'onde utilisee. Par contre, nos resultats dependent tres sensiblement de la valeur de la masse perturbative du quark charme et de la valeur moyenne du carre du moment relatif entre les deux quarks charmes. Les differentes fonctions d'ondes utilisees semblent, toutefois, preferer une masse perturbative sensiblement inferieur a la moitie de la masse du charmonium et une valeur moyenne du carre du moment relatif assez large. Ceci suggere finalement qu'un traitement relativiste de ces processus s'impose

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8

Hoferichter, Martin [Verfasser]. "Precision calculations for the low-energy dynamics of pions and nucleons / Martin Hoferichter." Bonn : Universitäts- und Landesbibliothek Bonn, 2012. http://d-nb.info/1044081163/34.

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9

Gibson, V. "The structure functions of free and bound nucleons in deep inelastic muon scattering." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376920.

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10

Vasseur, Olivier. "A microscopic treatment of correlated nucleons : collective properties in stable and exotic nuclei." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS223/document.

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Ce travail de doctorat s'inscrit dans le cadre des techniques adaptées à la résolution du problème à N corps nucléaire. Il a été motivé par la perspective d'utiliser des méthodes allant au-delà de l'approximation de champ moyen pour améliorer la description des spectres d'excitation des noyaux stables et exotiques, notamment les états de basse énergie et les résonances géantes. À cette fin, l'approche choisie est le développement de modèles basés sur la second random-phase approximation (SRPA) utilisée avec une procédure de soustraction. Ces développements ont pour but d'étendre le champ d'applicabilité du modèle initial et d'inclure des corrélations dans l'état fondamental.Une première partie consiste en l'application de la SRPA avec une méthode de soustraction à l'étude de la réponse dipolaire (comprenant la polarisabilité électrique dipolaire) et quadrupolaire de noyaux de masse moyenne à lourds. Nous vérifions que la SRPA avec soustraction corrige les problèmes observés avec la SRPA standard et améliore la description des spectres d'excitation, comparativement à la random-phase approximation (RPA). Nous étudions également les effets au-delà du champ moyen dûs à la SSRPA avec soustraction, en exploitant la relation entre les modes de respiration axiaux des noyaux et la masse effective de la matière nucléaire.Une seconde partie est dédiée à des extensions.Premièrement, nous étendons les outils numérique initiaux en utilisant l'approximation equal-filling (EFA) afin de permettre les applications aux noyaux ayant une orbitale partiellement occupée. Nous proposons ensuite une méthode d'estimation partielle des effets d'appariement en utilisant des nombres d'occupation corrélés.Une étude des moyens de renormaliser la SRPA avec soustraction est menée en employant un modèle allant au-delà de l'approximation de quasiboson. Cette extension est également basée sur l'utilisation de nombres d'occupation comme moyen d'inclure des corrélations dans l'état fondamental. Nous montrons que les corrélations obtenues par le calcul itératif en RPA des nombres d'occupation ne sont pas suffisantes pour corriger les problèmes de la SRPA standard
This Ph.D. work falls within the scope of theoretical techniques tailored to the solution of the nuclear many-body problem. It was motivated by the perspective of using beyond-mean-field methods to improve the description of excitation spectra of stable and exotic nuclei, especially the low-energy states and the giant resonances. The chosen path in this direction is the development of models based on the second random-phase approximation (SRPA) used with a subtraction procedure. These developments aim to extend the range of applicability of the initial model and to include correlations in the ground state.A first part consists in applying the SRPA used with a subtraction method to the study of the dipole and quadrupole response in medium to heavy-mass nuclei, including the electric dipole polarizability. We verify that the subtracted SRPA corrects the problems observed with the standard SRPA model and improves the description of excitation spectra compared to the random-phase approximation (RPA). We also study beyond-mean-field effects that arise in the subtracted SRPA by exploiting the relation between the axial breathing modes in nuclei and the effective mass in nuclear matter.A second part is dedicated to extensions.As a first step, we extend the initial numerical tools by employing the equal-filling approximation (EFA), to enable the applications to nuclei with partially-occupied orbitals. We next propose a method to estimate part of the pairing effects using correlated occupation numbers.A study of possible ways to renormalize the subtracted SRPA is carried out by employing a model which goes beyond the quasiboson approximation. This extension also relies on the use of occupation numbers as a means to include ground state correlations. We show that correlations obtained from the computation of occupation numbers in iterative RPA calculations are not sufficient to address the standard SRPA drawbacks

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11

Pierre, Nicolas. "Multiplicities of hadrons in deep-inelastic scattering of muons on nucleons at COMPASS." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS183/document.

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Un des buts de la collaboration COMPASS est l'étude de la structure de spin du nucléon. La question de la polarisation des quarks de la mer est un sujet capital en physique hadronique, en particulier pour la polarisation du quark étrange. En vue de mieux contraindre la polarisation des quarks, une connaissance précise des fonctions de fragmentation (FFs), qui expriment l'hadronisation d'un quark q en un hadron h dans l'état final, est nécessaire. Les FFs peuvent être extraites depuis les multiplicités de hadrons produites en diffusion inélastique profonde semi-inclusive (SIDIS). Les données ont été prises à COMPASS avec un faisceau de muons de 160 GeV/c diffusant sur une cible de protons pure (1H₂). La présente thèse présente les mesures des multiplicités de hadrons chargés (pions, kaons et protons) faites à partir des données SIDIS collectées en 2016. Elle détaille aussi les améliorations apportées au générateur d'événement DJANGOH dans le but d'améliorer la description des corrections radiative inclusive et semi-inclusive qui sont ensuite utilisées comme facteurs de corrections aux multiplicités. Les données couvrent un large spectre cinématique : Q² > 1 (GeV/c)², y ε [0.1,0.7], x ε [0.004,0.4], W ε [5,17] GeV et z ε [0.2,0.85]. Ces multiplicités, qui représentent un total d'environ 1800 points de données, apportent une contribution importante aux fit QCD globaux des données mondiales à NLO, visant à la détermination des FFs. Les FFs de quarks en kaons sont particulièrement attendues car elles pourront mieux contraindre la polarization du quark étrange
One of the goals of the COMPASS collaboration is the study of the nucleon spin structure. The question of the polarization of the sea quark is a burning issue in the hadronic physics, especially for the strange quark polarization. In order to better constrain the quark polarization, a precise knowledge of the quark Fragmentation Functions (FFs) into hadrons, which are the final state hadronisation of quark q into hadron h, is mandatory. The FFs can be extracted from hadron multiplicities produced in Semi-Inclusive Deep Inelastic Scattering (SIDIS). Data were taken at COMPASS from a 160 GeV/c muon beam scattering off a pure proton target (1H₂). This thesis presents the measurement of charged hadrons (pions, kaons and protons) multiplicities from SIDIS data collected in 2016. It also details the improvements brought to the DJANGOH event generator to better describe the inclusive and semi-inclusive radiative corrections in DIS that are then used as correction factors to the multiplicities. The data cover a large kinematical range : Q² > 1 (GeV/c)², y ε [0.1,0.7], x ε [0.004,0.4], W ε [5,17] GeV et z ε [0.2,0.85]. These multiplicities, which represent about 1800 data points in total, provide an important input for global QCD fit of world data at NLO, aiming at the FFs determination. The quark FFs into kaons are particularly awaited as they can better constrain the strange quark polarization

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12

Newberg, Lee Aaron. "Monte Carlo simulation of the nuclear to quark matter deconfinement transition of three quark nucleons." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/44594.

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13

Groenewald, Hendrikus Wilhelm. "A non-commutative walecka model as an effective theory for interacting nucleons of finite size." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20255.

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Thesis (MSc)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: The nite size of nucleons should play an important role in the description of high density nuclear matter as found in astro-physical objects. Yet we see that the Walecka model, which is generally used to describe these systems, treats the nucleons as point particles. Here we argue that a non-commutative version of the Walecka model may be a consistent and appropriate framework to describe nite nucleon size e ects. In this framework the length scale introduced through the non-commutative parameter plays the role of the nite nucleon size. To investigate the consequences of this description, the equations of motion and energy-momentum tensor for the non-commutative Walecka model are derived. We also derived an expression for the total energy of the system, as a function of the non-commutative parameter, in a spatially non-uniform matter approximation. The non-commutative parameter, as a variable dependent on the dynamics of the system, remains to be solved self-consistently.
AFRIKAANSE OPSOMMING: Die eindige grootte van nukleone moet 'n belangrike rol speel in die beskrywing van ho e-digtheid kern materie soos gevind in astro- siese voorwerpe. Tog sien ons dat die Walecka model, wat in die algemeen gebruik word om hierdie stelsels te beskryf, die nukleone as punt deeltjies hanteer. Ons redeneer dus dat 'n nie-kommutatiewe weergawe van die Walecka model 'n konsistente en gepaste raamwerk is om die e ekte van eindige nukleon grootte te beskryf. In hierdie raamwerk speel die lengte-skaal wat ingevoer word deur die nie-kommutatiewe parameter die rol van eindige grootte vir nukleone. Om die gevolge van hierdie beskrywing te ondersoek, word die vergelykings van beweging en die energie-momentum tensor afgelei vir die nie-kommutatiewe Walecka model. Ons het ook 'n uitdrukking vir die totale energie van die stelsel, as 'n funksie van die niekommutatiewe parameter, afgelei in 'n ruimtelik nie-uniforme materie benadering. Die niekommutatiewe parameter, as 'n veranderlike afhanklik van die dinamika van die stelsel, bly steeds om self-konsistent opgelos te word.

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14

Barz, Ligia Liani. "Emissão de nucleons via mecanismo de Feshbach-Zabeck na colisão periférica de íons pesados relativísticos." Universidade de São Paulo, 1990. http://www.teses.usp.br/teses/disponiveis/43/43131/tde-17042014-132754/.

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O mecanismo de \"troca de fônon\" de Feshbach e Zabek é revisto e uma discussão detalhada é fornecida sobre o papel das leis de conservação e relação \"tipo fônon\" entre energia e momento transferidos. São investigados os efeitos de correlações de curto alcance na emissão de nucleons em colisões periféricas de íons pesados relativísticos. A seção de choque é calculada na aproximação de Born usando uma adaptação conveniente do modelo de Karol para o estado inicial e ondas planas, explicitamente ortogonalizadas ao estado inicial, para estados finais. Comparações com os resultados obtidos por Bertulani et al. usando ondas planas puras para o estado final mostram que a ortogonalização desempenha um papel relevante no valor obtido para a seção de choque. Discute-se também a sensibilidade do resultado aos parâmetros usados na discussão do estado inicial.
Abstract The \"phonon exchange\" mechanism of Feshbach and Zabek is reviewed and the role of the conservation laws and of the \"phonon-like\" relation between energy and transfered momentum is discussed. The effects of short range correlations for the emission of pair in peripheral relativistic heavy ions collisions are investigated. The cross section is calculated in Born approximation using a suitable modification of Karol\'s model for the initial state and plane waves, explicitly ortogonalized to the initial state, for the final states. Comparisons with the results obtained by Bertulani et al. using pure plane waves for the final state show that the ortogonalization has a non-negligibe effect on the magnitude of the resulting cross-sections. Sensitivity to the parameters involved in the description of the initial state is also discussed.

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Matthew, Burrows B. "Ab Initio Leading Order Effective Interactions for Scattering of Nucleons From Light Nuclei." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1600945141719748.

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16

Hazelton, William Donald. "Configuration mixing of quark states in nucleons and other baryons in the MIT bag model /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/9770.

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17

Kobzak, Sergei [Verfasser], and Adriana [Akademischer Betreuer] Pálffy. "Transition from bound to single independent nucleons in strong fields / Sergei Kobzak ; Betreuer: Adriana Pálffy-Buß." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://nbn-resolving.de/urn:nbn:de:bsz:16-heidok-286646.

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FERREIRA, Joacy Vicente. "Aplicações de métodos de química quântica: adsorção de H2 em Pd e um modelo para nucleons." Universidade Federal de Pernambuco, 2008. https://repositorio.ufpe.br/handle/123456789/9345.

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Made available in DSpace on 2014-06-12T23:14:14Z (GMT). No. of bitstreams: 2 arquivo4324_1.pdf: 2449805 bytes, checksum: 94f5f2f7a2d78c8943830784876dc44d (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A Química Quântica tem oferecido marcantes e variadas contribuições na descrição e previsão de inúmeros fenômenos da natureza. Referendando tal potencialidade, utilizamos neste trabalho os métodos de química quântica para abordar dois temas bastante distintos: adsorção de H2 em Pd e a descrição de nucleons através de um modelo molecular. Baseado na teoria do funcional da densidade e na teoria da ressonância nãosincronizada de Pauling descrevemos os estados moleculares envolvidos no mecanismo de adsorção e dissociação de H2 em superfície de paládio. Apesar de utilizarmos modelos de cluster extremamente simples (a superfície foi representada por um, dois e cinco átomos de Pd), os resultados foram bastante úteis para explicar a adsorção da molécula de hidrogênio e para mostrar, de forma inédita, que o estado pré-dissociativo corresponde à molécula adsorvida numa geometria inclinada em relação à superfície. Além desse estudo de adsorção, também mostramos a utilidade da química quântica na descrição de sistemas exóticos envolvendo quarks. Elaboramos um modelo molecular quark-boson bastante original para descrever o próton e o nêutron. Através de cálculos ab initio Hartree-Fock obtivemos curvas de energia potencial muito bem comportadas para os sistemas quark-boson propostos. Assim, foi possível calcular as dimensões dos nucleons e reproduzir a diferença de massa nêutron-próton em excelente concordância com o valor experimental

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Kobzak, Sergei [Verfasser], and Adriana [Akademischer Betreuer] Pálffy-Buß. "Transition from bound to single independent nucleons in strong fields / Sergei Kobzak ; Betreuer: Adriana Pálffy-Buß." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/1216446164/34.

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Nasri, Amine. "Microscopic nonlocal potentials for the study of scattering observables of nucleons within the coupled channel framemork." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS273/document.

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Une bonne compréhension et une bonne capacité de prédiction de la section efficace de diffusion de neutron est essentielle à un grand nombre de technologies nucléaires, parmi lesquelles les réacteurs à fission. Pour les noyaux déformés, le calcul des observables de diffusion de nucléon pour la voie élastique et les premiers états excités de basse énergie requiert l'utilisation de calcul en voies couplées. Des potentiels optique et de transition phénoménologiques locaux sont le plus couramment utilisés dans les analyses par voies couplées, mais leur précision en dehors de leur domaine d'ajustement est imprévisible. Des approches microscopiques sont en cours de développement pour augmenter les capacités prédictives et résoudre les problèmes d'extrapolation. Un potentiel obtenu microscopiquement est non local, et de récentes études ont souligné l'importance de traiter explicitement cette non localité sans passer par une procédure de localisation. Notre but dans ce travail est d'étudier dans une approche microscopique, sans paramètre ajustable, l'impact de la non localité des potentiels sur les observables de diffusion de nucléon sur noyau cible. Pour ce faire, nous étudions la diffusion de neutron avec la matrice G de Melbourne qui représente l'interaction entre le projectile et un nucléon de la cible, et nous utilisons la RPA pour décrire la structure de la cible dans le cadre de nos premières applications sur le ⁹⁰Zr. Pour pouvoir étudier aussi des noyaux déformés, nous menons notre étude dans le cadre des voies couplées. La première partie de ce document contient la dérivation, faite dans un cadre unique et cohérent, des équations couplées pour la diffusion de nucléons et des potentiels microscopiques obtenues avec la matrice G de Melbourne et une description de la cible via la RPA. La deuxième partie est dédiée à la présentation des codes que nous avons développés durant ce projet de thèse : MINOLOP pour le calcul de potentiels microscopiques à partir de la matrice G de Melbourne et d'informations de structure données sous la forme d'une densité à 1 corps, et ECANOL pour la résolution des équations en voies couplées avec des potentiels non locaux en entrée. Enfin, nous présentons nos premières applications basées sur ces deux codes : l'étude d'émission de pré-équilibre due à des excitations à 2 phonons dans le ⁹⁰Zr
A good understanding and prediction capacity of neutron scattering cross sections is crucial to many nuclear technologies, among which all kinds of reactors based on fission process. For deformed nuclei, the computation of scattering observables for the elastic channel and the first, low-lying excited states requires coupled channel calculations. Local, phenomenological optical and macroscopic transition potentials are the most commonly used in coupled channel analyses, but their accuracy outside of their fitting range remains unpredictable. Microscopic approaches are being developed in order to improve prediction power and solve the extrapolation issue. Potentials obtained microscopically are nonlocal, and recent studies have emphasized the importance of treating explicitly this nonlocality, without using a localization procedure. Our goal in the present work is to study in a quantum framework with no adjustable parameter, the impact of the nonlocality of potentials on scattering observables of nucleon-nucleus reactions. To achieve this we study neutron scattering with the Melbourne G matrix, which represents the interaction between the projectile and one nucleon of the target, and we describe the target’s structure using the RPA for our first applications to ⁹⁰Zr. In order to be able to study also deformed nuclei, we do our study in the coupled channel framework. The first part of this paper is dedicated to the derivation in a unique, consistent scope of coupled equations for nucleon-nucleus scattering and of the potentials obtained with the Melbourne G matrix and RPA structure input. Secondly, we describe the codes which we wrote during this Ph.D. project: MINOLOP for the computation of microscopic potentials using the Melbourne G matrix and structure inputs given in terms of a 1-body density, and ECANOL for the resolution of coupled channel equations using nonlocal potentials as input. Eventually, we present our first applications using these two codes to study pre-equilibrium emissions due to 2-phonon excitations in ⁹⁰Zr

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Persram, Declan. "Delta production in nucleon-nucleon scattering and pion production in nucleus-nucleus collisions." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23931.

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We present a calculation of $ Delta$ production cross section in the one-boson-exchange model for the reaction $NN to N Delta.$ Our calculation is in quantitative agreement with a previous calculation by Huber and Aichelin (1). The effect of the $NN to N Delta$ anisotropic differential cross section on $ pi$ production in Au + Au collisions at a kinetic energy of $1{GeV over A}$ is studied. We find that there is no large effect on the final $ pi$ transverse momentum spectra.

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22

Zwirn, Hervé. "Modele phenomenologique unifie pour les interactions fortes, faibles et electromagnetiques des pions, des nucleons et des leptons." Paris 6, 1988. http://www.theses.fr/1988PA066622.

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Devant les difficultes que rencontrent les techniques non perturbatives dans q. C. D. , il parait interessant d'adopter une approche differente par l'utilisation de lagrangiens effectifs permettant de predire les proprietes des hadrons usuels comme le pion ou le nucleon a basse energie. L'objectif de ce travail est de fournir dans une premiere etape, un lagrangien effectif renormalisable, qui s'appuie sur un modele de jauge, pour les interactions fortes du pion, du nucleon et des mesons rho et al. Puis, dans une deuxieme etape, d'etendre ce modele aux interactions electrofaibles de ces particules et des leptons. Il est ensuite utilise pour calculer les differences de masses electromagnetiques pour le pion et le nucleon

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23

Lima, Ana Cecilia de Souza. "Fotoprodução de kaons e híperons em deutério." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-18022014-150328/.

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Com o objetivo de investigar a fotoprodução de kaons na região de energias intermediarias, foram realizadas medidas de seção de choque de fotoprodução de híperons utilizando o deutério como alvo, entre 0,50 e 2,95GeV. Para obtenção das medidas foi utilizado o acelerador de elétrons do TJNAF (Thomas Jefferson National Accelerator Facility) localizado na Virginia, USA. Foram obtidas seções de choque de fotoprodução para as reações gama(p, K+)lambda, gama(p, K+)sigmaº, sigma(n, K+)lambda-. Observou-se a estrutura de interferência na proximidade do limiar de produção de \'lambdaº, previsto teoricamente. As seções de choque obtidas foram comparadas com o modelo teórico existente fornecendo informações fundamentais para uma elaboração teórica mais consistente. Foram ainda, observados lambda(1385) com grande resolução abrindo possibilidade de realizar um estudo muito interessante desta produção.
Kaon photoproduction on deuterium was investigated and the differential cross sections were determined using the data obtained in Hall B at TJNAF (Thomas Jefferson National Accelerator Facility). Real photons were produced in the range covered from 0.50 to 2.95GeV. The cross section for kaon production reactions gama(p, K+ ) lambda, gama(p, K+ ) \'sigmaº, sigma(n, K+)lambda- were obtained. The interference structure near the production of lambdaº, predicted theoretically, was revealed. Theoretical model was compared to the cross section obtained and fundamental informations became available in order to improve the consistence of the model existent. At last, lambda(1385) were identified with good resolution conducting to interesting investigation in the future.

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24

Maurer, Thilo [Verfasser], and Andreas [Akademischer Betreuer] Schäfer. "The QPACE supercomputer, renormalization of dynamical CI fermions, axial charges of excited nucleons / Thilo Maurer. Betreuer: Andreas Schäfer." Regensburg : Universitätsbibliothek Regensburg, 2011. http://d-nb.info/102287229X/34.

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25

Niyazov, Rustam. "Measurements of Correlated Pair Momentum Distributions in {sup 3}He(e,e{prime}pp)n with CLAS." Washington, D.C : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Energy Research ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2003. http://www.osti.gov/servlets/purl/824882-21uB5k/native/.

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Thesis (Ph.D.); Submitted to Old Dominion Univ., Norfolk, VA (US); 1 May 2003.
Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-36" "DOE/ER/40150-2739" Rustam Niyazov. 05/01/2003. Report is also available in paper and microfiche from NTIS.

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26

Smidt, Samantha. "Determination of the ration gA/gV in neutron decay and the interactions of positive kaons and nucleons and nuclei." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364141.

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27

Shim, Sugie. "Relativistic analyses of inelastic nucleon-nucleus scattering /." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487672631598132.

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28

Клок, О. В. "Теорія струн." Thesis, Сумський державний університет, 2014. http://essuir.sumdu.edu.ua/handle/123456789/38841.

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На початку ХХ століття Альберт Ейнштейн створив теорію відносності у тривимірному просторі, яка була розширена математиком Теодором Калуцом. Він запропонував сміливу ідею, що наш всесвіт може мати більше ніж три. З іншого боку на основі робот Гейзенберга, Дірака, Шреденгера та інших була створена квантова механіка. На стику цих двох розділів фізики виникла проблема загальної теорії яка полягала в тому, що ці розділи існують окремо один від іншого. Для вирішення цієї проблеми була запропонована теорія струн.

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29

Tullney, Kathlynne [Verfasser]. "Search for a spin-dependent short-range force between nucleons with a 3 He, 129 Xe clock-comparison experiment / Kathlynne Tullney." Mainz : Universitätsbibliothek Mainz, 2014. http://d-nb.info/1048212122/34.

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30

LE, GOFF JEAN-MARC. "Etude de l'interaction a courte distance entre deux nucleons dans les noyaux d'helium-3 et d'helium-4 par la diffusion (e,ep)." Paris 11, 1991. http://www.theses.fr/1991PA112397.

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La section efficace de la reaction #4he(e,ep)x a ete mesuree pour des impulsions de recul comprises entre 225 et 500 mev/c. Cette experience met clairement en evidence des paires de nucleons en interaction a courte distance a l'interieur du noyau d'helium-4. Du point de vue cinematique, le continuum presente une structure en bosse qui se deplace avec l'impulsion de recul de facon caracteristique. Du point de vue dynamique, on observe un bon accord entre les donnees et un calcul microscopique qui prevoit que la diffusion sur une paire en interaction est le processus dominant. De plus, au-dela de 250 mev/c, la distribution d'impulsion dans le continuum apparait tres proche de la distribution d'impulsion du deuterium. Par ailleurs, nous avons teste notre comprehension du mecanisme de reaction en effectuant une separation des composantes transverse et longitudinale pour la reaction #3he(e,ep)x a la plus haute impulsion de recul possible, 260 mev/c. La reponse longitudinale apparait proche de l'approximation d'onde plane. On observe en revanche un exces transverse important et qui n'est que partiellement reproduit par un calcul microscopique incluant l'interaction dans l'etat final et les courants d'echange. Notons cependant que les mesures sans separation ont ete realisees dans une region cinematique ou la partie longitudinale domine

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31

Roudot, François. "Contribution a l'etude des mesons et de leur interaction avec les noyaux, par production au seuil dans les systemes a petit nombre de nucleons." Paris 11, 1995. http://www.theses.fr/1995PA112053.

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La courbe d'excitation au seuil de la reaction p+dhelium-3+x ainsi que la section efficace totale de production du meson au voisinage du seuil dans la reaction d+dalpha+eta ont ete mesurees sur la ligne de detection spes4 du laboratoire national saturne. Dans la premiere etude, des signaux clairs sont observes aux seuils des mesons omega, eta' et phi ; des structures apparaissent aux masses centrales des mesons a-zero et f-zero ainsi qu'au-dessus du seuil de production de deux kaons. Elles pourraient etre la signature d'etats hadroniques exotiques. Le fond physique de production a deux pions et deux kaons a ete evalue dans un modele de pion echange permettant de calculer les sections efficaces differentielles de la reaction elementaire pi-zero+pn+x ; les resultats rendent bien compte des observations faites pour ce processus elementaire. Ces resultats extrapoles a la reaction p+dhelium-3+x ou x correspond a deux pions ou deux kaons permettent d'expliciter le fond physique de la courbe d'excitation au seuil. En ce qui concerne la seconde etude, le meson a ete clairement observe sur les spectres au plan focal final du spectrometre, en bon accord avec une simulation monte carlo ; une section efficace totale de l'ordre du nanobarn a ete mesuree. Les resultats sont compares a divers processus de production du meson eta mettant en jeu des noyaux plus legers que l'helium-4. Une etude comparative de l'interaction eta-noyau sur ces differents noyaux a ete realisee faisant apparaitre un caractere plus attractif dans le cas de l'helium-4. Grace a ces mesures, la brisure de la symetrie de charge dans la reaction d+dalpha+pi-zero a ete abordee ; en utilisant un modele de melange des mesons pi-zero et eta, les sections efficaces extraites sont compatibles avec la seule mesure de la section efficace de cette reaction

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32

Nedjadi, Youcef. "Elektroweak tests of the relativistic nuclear scalar-vector model." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236201.

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33

Fraser, Paul R. "Development and application of a multi-channel algebraic theory for nucleon-nucleus scattering /." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/3597.

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34

Geßler, Stefanie [Verfasser]. "Hadron-Nucleus interactions in the nucleon resonance region / Stefanie Geßler." Gießen : Universitätsbibliothek, 2017. http://d-nb.info/1141053349/34.

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35

Cunningham, Elizabeth Sarah. "The effect of spin-spin interactions on nucleon-nucleus scattering." Thesis, University of Surrey, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527010.

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36

Rocha, Alberto Sperotto dos Santos. "Um modelo de sacola difusa para a matéria nuclear." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2004. http://hdl.handle.net/10183/6706.

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Neste trabalho desenvolvemos um modelo efetivo para a descrição da matéria nuclear, que incorpora os resultados obtidos, para a descrição de um núcleon, pelo modelo de sacola difusa. O sistema nuclear será descrito via uma função de energia interna, que compreende um termo livre e outro que leva em conta a interação entre os núcleons. A parte livre, por se tratar de um sistema de férmions, corresponderá à energia de um gásde Fermi livre. Além disso, para evitar a superposição de dois ou mais núcleons, introduzimos um volume de exclusão a la Van der Waals. Na parte integrante, a troca de píons entre os núcleons será levada em conta via um potêncial efetivo. A função energia interna dependerá da densidade da matéria nuclear e também de um parâmetro que determinará o volume esperado de cada núcleon na matéria nuclear. O valor deste parâmetro será um pouco diferente do valor encontrado para um núcleons isolado, devido à interação entre eles. Obtém-se então resultados para a energia de ligação por núcleon para a matéria nuclear simétrica e para a matéria de nêutrons, bem como para a equação de estado da matéria de nêutrons.

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37

Tallini, Hugh Arthur McLaren. "A measurement of the quark spin distributions of the nucleon at HERMES." Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367159.

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38

Son, Hyeon-Dong [Verfasser], Maxim [Gutachter] Polyakov, and Hyun-Chul [Gutachter] Kim. "Parton quasi-distributions and energy-momentum tensor form factors for large Nc nucleons / Hyeon-Dong Son ; Gutachter: Maxim Polyakov, Hyun-Chul Kim ; Fakultät für Physik und Astronomie." Bochum : Ruhr-Universität Bochum, 2021. http://d-nb.info/1240479239/34.

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39

Rahnama, M. "Photoproduction of single-charged pions from nucleons in the kinematical region : E#Ì²gamma#'LAB up ton 20 GeV and 0.0 #< =# -t#approx =# 1.0 (GeV/C)'2." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377675.

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40

Chai, Zhengwei. "Study of the N to Delta Transition via p({rvec e}, e'{rvec p}){pi}{sup 0} Reaction." Washington, D.C : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Energy Research ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2003. http://www.osti.gov/servlets/purl/816501-VTYjov/native/.

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Thesis (Ph.D.); Submitted to the Massachusetts Inst. of Tech., Cambridge, MA (US); 1 Oct 2003.
Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-174" "DOE/ER/40150-2571" Zhengwei Chai. 10/01/2003. Report is also available in paper and microfiche from NTIS.

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41

Hlophe, Linda D. "Separable Representation of Nucleon-Nucleus Optical Potentials as Input to (d,p) Reaction Calculations." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1467319283.

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42

Bailey, Gregory William. "Nonlocal nucleon-nucleus interactions in (d,p) reactions : the role of the deuteron d-state." Thesis, University of Surrey, 2016. http://epubs.surrey.ac.uk/813009/.

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Traditional (d,p) reaction models use local optical model potentials to represent the deuteron-target interaction. Within such models, the deuteron d-state contributes little to differential cross sections, as local potentials are only sensitive to low n-p relative momenta. However, recent work by Timofeyuk and Johnson, that includes the inherent nonlocality of the nucleon-target optical model potentials, suggests this is not true of nonlocal models which include deuteron breakup. This study showed that nonlocal deuteron-target potentials, found with a pure s-state deuteron, are influenced by large n-p relative momenta. The d-state can dominate the deuteron wavefunction at high momenta, suggesting d-state effects could be significant in nonlocal reaction calculations. This work incorporates the d-state into deuteron-target potentials, in the presence of nonlocal nucleon-target interactions and breakup. This is found using energy independent nonlocal nucleon-target optical model potentials of the Perey-Buck type. Deuteron channel distorted waves can then be found and used to calculate differential cross sections. The proton channel is constructed in the same manner. It is shown that the d-state effects from the central part of the deuteron-target potentials significantly alter calculated differential cross sections, when compared to nonlocal pure s-state calculations. The d-state also produces a tensor component of the deuteron-target potential, but this has negligible effects on cross section calculations. The choice of nucleon-nucleon potential, used to construct the deuteron wavefunction, is also investigated. It is shown that, within this works approach, calculated differential cross sections are sensitive to this choice. This is because the resulting wavefunctions have different high momentum behaviors. This sensitivity is shown to be enhanced if the final state of the transfered neutron has a large separation energy. This work concludes that in nonlocal (d,p) reaction models, which include break-up effects, the deuteron d-state gives a significant contribution to the deuteron-target potentials. The inclusion of nucleon-nucleus nonlocality in the deuteron-target potentials has produced sensitivity to the high momentum components of the deuteron wavefunction, where the d-state can dominate. The high momentum structure of the deuteron wavefunction differs between N-N models. As such, differential cross sections from this works approach can significantly change depending on the choice of deuteron wavefunction.

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43

MAZZOCCA, MATTEO. "Ruolo dell'organizzazione nucleare nel meccanismo di ricerca e di regolazione genica mediata da p53." Doctoral thesis, Università Vita-Salute San Raffaele, 2022. http://hdl.handle.net/20.500.11768/133069.

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Un aspetto irrisolto in biologia molecolare è come l'organizzazione del nucleo regoli l'espressione genica. Nelle sue primissime fasi, l’espressione genica richiede che fattori di trascrizione scansionino il genoma -fra una miriade di DNA non specifico- per trovare geni specifici, un processo che culmina con l'associazione a promotori ed enhancer. I batteri hanno sviluppato speciali meccanismi per eludere l'effetto "sequestrante" del DNA non specifico e accelerare la ricerca, rendendo il processo estremamente efficiente. Non è noto se fattori di trascrizione eucariotici condividano meccanismi simili, né se il nucleo formi compartimenti che facilitano il loro reclutamento. Studi recenti in cellule umane suggeriscono che i fattori di trascrizione regolino il loro processo di ricerca attraverso interazioni deboli con l'ambiente circostante, ma non è chiaro con quali compartimenti nucleari. In questo studio caratterizziamo il meccanismo di ricerca di p53, un fattore di trascrizione umano con importanti funzioni antitumorali, che regola molteplici vie di segnalazione a seguito di danno al DNA, come ad esempio l'arresto del ciclo cellulare e l'apoptosi. Per affrontare questo problema applichiamo una nuova tecnologia di imaging in vivo, che permette di seguire in tempo reale il meccanismo di ricerca di p53 in vari compartimenti nucleari. L'approccio combina una tecnica a singola molecola (single molecule tracking, SMT) -per studiare le interazioni di singole molecole di p53 nel nucleo- con un metodo per mappare compartimenti nel nucleo ad alta risoluzione (multifocal structured-illumination, mSIM). I nostri risultati indicano che p53 "percepisce" la conformazione dell'ambiente nucleare attraverso contatti mediati dalle sue regioni intrinsecamente disordinate. Queste interazioni guidano p53 attraverso compartimenti di cromatina a diversa permeabilità, portandola rapidamente sui suoi geni target per regolarne l'espressione.
A fundamental question in molecular biology is how the organization of the cell nucleus regulates gene expression. In its first steps, gene regulation requires transcription factors (TFs) to scan the genome -among a myriad of DNA random sequences- and find their targets, a process culminating with the association to specific promoters and enhancers. Bacteria have evolved special molecular mechanisms to elude the ‘sequestering’ effect of random DNA and speed up the TF search, making gene regulation extremely efficient. Whether eukaryotic TFs share similar mechanisms, how they find and selects their targets and whether the nucleus define local compartments that may facilitate or exclude their recruitment, is poorly understood. Recent evidence points out that TFs can engage weak and dynamic interactions with the surrounding environment, modulating the search process, but it is unclear what nuclear substructures are involved. In this work we characterize how the human tumor suppressor p53 – an important TF regulating multiple pathways in response to DNA damage such as cell cycle arrest, senescence and apoptosis – searches for its target genes in the cell nucleus, and how nuclear organization controls this process. We apply a novel fluorescence live imaging technology to follow in real-time the search process of p53 through nuclear compartments. The approach combines single molecule tracking (SMT) -to study the dynamic interactions in living nuclei of individual p53 molecules- with multifocal structured-illumination (mSIM), to map distinct compartments in the nucleus at high resolution. We find that p53 ‘perceives’ the conformation of the nuclear environment through contacts mediated by its intrinsically disordered regions (IDRs). These interactions guide p53 through chromatin compartments of different permeability, to efficiently locate p53 targets and induce gene expression.

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44

Sánchez, Sánchez Mario. "Théories effectives des champs pour systèmes avec interaction forte : diffusion des nucléons et états liés de quarks lourds." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS419/document.

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Au cours des dernières décennies, des théories effectives des champs (TEC) ont été largement utilisées comme approche de la physique à interaction forte et à faible énergie (régimes nucléaires et hadroniques). Dans cette thèse, nous explorons en détail trois exemples d'applications du programme des TEC au système NN dans l'état de spin singulet (onde S et ondes périphériques respectivement) et aux molécules théorisées de mésons lourds DDs0* et D*Ds1*
During the last few decades, effective field theories (EFT) have been widely used as an approach to low-energy strong-interacting physics (nuclear and hadronic regimes). In this thesis, we will explore in detail three examples of applications of the EFT program to the spin-singlet NN system (S wave and peripheral waves respectively) and to the theorized heavy-meson molecules DDs0* and D*Ds1*

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45

Niccolai, Silvia. "Three-body Forces in Photoreactions on 3He." Washington, D.C : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Energy Research ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2003. http://www.osti.gov/servlets/purl/824932-PJ4Kr6/native/.

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Thesis; Thesis information not provided; 1 Feb 2003.
Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-39" "DOE/ER/40150-2763" Silvia Niccolai. 02/01/2003. Report is also available in paper and microfiche from NTIS.

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46

Zhang, Bin. "Searching for Short Range Correlations Using (e,e'NN) Reactions." Washington, D.C : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Energy Research ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2003. http://www.osti.gov/servlets/purl/824928-2353Al/native/.

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Thesis; Thesis information not provided; 1 Feb 2003.
Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-38" "DOE/ER/40150-2762" Bin Zhang. 02/01/2003. Report is also available in paper and microfiche from NTIS.

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47

Cavalcante, Isabela Porto. "A Interação Nucleon-Nucleon no Modelo de Skyrme." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/43/43131/tde-27022014-143037/.

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A interação forte a baixas energias pode ser abordada por meio de lagrangianas efetivas. Nesse contexto, o modelo de Skyrme representa uma forma de descrever bárions, que emergem como sólitons topológicos de uma lagrangiana mesônica quiral. A interação nucleon-nucleon (NN) é comumente tratada neste modelo de maneira aproximada, através do chamado Ansatz Produto (AP), cujo problema mais sério é não reproduzir a atração de alcance intermediário no canal escalar-isoescalar do potencial NN. O objetivo deste trabalho é construir um novo ansatz para o cálculo da interação NN no modelo de Skyrme. Para isso, analisamos o AP, investigando as causas deste problema fenomenológico, e concluímos que deve-se à componente azimutal de seu campo piônico. A partir disto, construímos o Ansatz Novo (AN), com o qual calculamos o novo potencial. Comparando os resultados com outros potenciais existentes, mostramos que o AN constitui uma solução plausível para o problema.
Strong interactions at low energies can be treated by means of effective lagrangians. In this context, the Skyrme model is regarded as a way to describe baryons as topological solitons from a chiral mesonic lagrangian. In the framework of this model, nucleon-nucleon (NN) interaction is usually derived in the sudden approximation, by means of the so called Product Ansatz (PA). Its most serious problem is the absence of the intermediate range attraction in the scalar-isoscalar channel of the NN potential. We construct a new ansatz to derive the NN interaction in the Skyrme model. At first, we analise the PA and investigate the causes of its phenomenological problem. We conclude it is due to the azimuthal component of its pionic field. With this result we build the New Ansatz (NA) and calculate the new potential. Comparisons of the results with other existent potentials show that NA constitutes a plausible solution to the problem.

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48

ROSSI, JUNIOR ERNESTO S. "Determinacao experimental do potencial nucleo-nucleo e da densidade do projetil sup(18)O, por meio do espalhamento quase-elastico em nucleos-alvos na camada f-p." reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10914.

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Made available in DSpace on 2014-10-09T12:45:29Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T13:56:01Z (GMT). No. of bitstreams: 1 07295.pdf: 6617875 bytes, checksum: 02bc676c5e25a80397e40d7d6eecf61d (MD5)
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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49

Haapakoski, Pekka. "The nucleon-nucleon and nucleon-antinucleon interactions in two-body and in many-body systems." Oulu : University of Oulu, 1987. http://catalog.hathitrust.org/api/volumes/oclc/60080858.html.

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50

Vuong, Au Kim. "New Skyrme nucleon-nucleon interaction for the mean-field approximation." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5996.

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The effective Skyrme type interactions have been used in the mean-field models for several decades, and many different parameterizations of the interaction have been realized to better reproduce nuclear masses, radii, and various other data. Today, there are more experimental data of nuclei far from the B stability line. It is time to improve the prediction power of the Skyrme type effective nucleon-nucleon interactions. In this dissertation, we present the procedure of the fitting of the mean-field results to an extensive set of experimental data with some constraints on the Skyrme parameters and some approximations in the Hartree-Fock mean-field to obtain the parameters of the new Skyrme type effective interactions, namely, KDE and KDE0. We investigate the long-standing discrepancy of more than 20% between the values of the incompressibility coefficient Kn:m: obtained within relativistic and non-relativistic models. We show that this difference is basically due to the differences in values of the symmetry energy coefficient J and its slope L associated with the relativistic and non-relativistic models. We also present the results of fully self-consistent Hartree-Fock based Random Phase Approximation calculations for the centroid energies of the breathing modes in four nuclei, namely, 90Zr, 116Sn, 144Sm, 208Pb, obtained with our new Skyrme interaction KDE0. A good agreement with the experimental data is achieved.

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