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An Axis Through Nature: Ranger Station at Pandapas PondTodd, Alan Curry 08 May 2007 (has links)
My thesis is a human intervention into the tranquil and natural environment of Pandapas Pond and the Jefferson National Forest. Although the form of the intervention embraces the landscape and natural land formations, its purpose is to take the visitor along a path that translates the experience from one of participation to that of observation of the parkâ s surroundings. This is both an investigation of an architectural integration with the site and a partial separation of the inhabiter from his/her natural surroundings. / Master of Architecture
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Reproduction, Survival, and Denning Ecology of Black Bears in Southwestern VirginiaRyan, Christopher W. II 29 January 1998 (has links)
Thirty-four (6 M, 28 F) of 93 black bears (<i>Ursus americanus</i>) captured during summers 1995 and 1996 were equipped with radio-collars. The mean age of male and females captured was 2.5 (<u>n</u> = 63; 2 males not aged) and 4.4 (<u>n</u> = 28) years, respectively. The mean date of females in estrus was 24 July, and we observed one 1.5-year old female in estrus. The average age of primiparity of radio-collared females was 3.0 years; however, we documented fetuses present in a 2-year old noncollared female's reproductive tract. The average interbirth interval was 1.6 years and 95.4% of females without yearlings produced cubs. The mean litter size was 2.2 and the cub sex ratio was 1.3M:1F.
Hunting, vehicle collisions, poaching, research, and euthanasia accounted for 80.5%, 5.5%, 5.5%, 5.5%, and 2.8%, respectively of the adult and juvenile male mortalities (<u>n</u> = 36). Hunting, vehicle collisions, and research each accounted for 2 of the adult and juvenile female mortalities (<u>n</u> = 6). Annual harvest rates for males in 1995 and 1996 were 36.1% and 45.5%, respectively; corresponding harvest rates for females were 0.0%, and 5.9%. Annual survival rates estimated with Kaplan-Meier for adult females, juvenile females, and cubs were 100.0%, 93.3%, and 70.3%, respectively. Maximum juvenile male survival rates were 52.0% in 1995 and 51.7% in 1996. Maximum adult male survival rates were 50.0% and 80.0% in 1995 and 1996, respectively.
We monitored 31 bears for 39 bear winters with 100% of the known bears denning. Bears denned in trees (41%), rock cavities (32%), excavations (14%), snags (8%), and ground nests (5%). Chestnut oak (<i>Quercus prinus</i>; <u>n</u> = 9), red oak (<i>Q. rubra</i>; <u>n</u> = 8), and tulip-poplar (<i>Liriodendron tulipifera</i>; <u>n</u> = 1) were used as tree dens. Habitat characteristics did not differ between ground dens and tree dens; however, older bears used ground dens more frequently (<u>Z</u> = -2.484, <u>P</u> = 0.013) than tree dens. Fifty-seven percent of bears denned on public land, and we documented one instance of den reuse. / Master of Science
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[en] THE SEPARATION OF POWERS FROM THE AMERICAN REVOLUTION TO THE CONSTITUTION OF THE UNITED STATES: THE DEBATE OVER THE JEFFERSON S, MADISON S AND HAMILTON S CONSTITUTIONAL PROJECTS / [pt] A SEPARAÇÃO DE PODERES DA REVOLUÇÃO AMERICANA À CONSTITUIÇÃO DOS ESTADOS UNIDOS: O DEBATE ENTRE OS PROJETOS CONSTITUCIONAIS DE JEFFERSON, MADISON E HAMILTONFERNANDO RAMALHO NEY MONTENEGRO BENTES 22 February 2008 (has links)
[pt] A Revolução Americana registrou uma intensa participação
política
popular nos Estados da Confederação. Este período marcou a
preferência pela
doutrina da separação absoluta de Poderes, uma vez que o
sistema de governo
balanceado inglês permitiu que o clientelismo real
corrompesse a independência
do Parlamento, órgão supostamente responsável pela defesa
das liberdades civis
nas colônias. Porém, o engajamento do povo foi condenado
pela elite norteamericana,
que liderou um movimento de centralização do poder capaz de
controlar o excesso de democracia local, identificado com
a supremacia que as
assembléias possuíam no âmbito estadual. Neste contexto
surge a Constituição de
1787, que funda suas bases na teoria dos freios e
contrapesos como um método de
fiscalização recíproca dos Poderes, mas, com especial
destaque, para o controle do
Legislativo. O evento constitucional enfraqueceu a virtude
dos cidadãos, que se
restringiu à atividade de expansão rumo à fronteira e
criou um mecanismo de
governo autônomo, que concentrou a política na ação de uma
elite dirigente e na
relação entre os diferentes órgãos intra-estatais. O
estudo da concepção de
separação de Poderes em Jefferson, Madison e Hamilton
ajuda a esclarecer o
modo com que o projeto constitucional de 1787 rompeu com a
ideologia a
essência revolucionária. / [en] The American Revolution presented a high level of popular
politics
participation under the Confederation years. This moment
marked the option for
the absolute doctrine of the separation of powers as a
response against the failure
of the balanced constitution theory and the incapacity of
the British Parliament to
protect the colonies civil liberties. However, the fear of
popular engagement made
the American elites lead a centralization of power that
could be able to control the
popular local democracy. The Constitution of the United
States and its checks and
balances system were born as a result of that conservative
process. The
constitutional structure protected the government of the
people direct action and
influence, creating a separated dimension to the politics
forces game. The study of
the concepts of this era and the meanings they were used,
particularly, the
Jefferson s, Madison s and Hamilton s conception
concerning of the separation of
powers doctrine helps to understand how the Constitution
ruptured the spirit of the
American Revolution, based on the active citizenship.
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An Uneasy Alliance: the Relationship Between Jefferson and Burr: 1791-1807Helms, Dorcas K. 08 1900 (has links)
Papers, memoirs, diaries, letters and autobiographies from 1791-1807 are studied to determine the relationship between Jefferson and Burr. A limited examination of congressional records for the same period was made. Monographs and biographies of Jefferson, Burr and their contemporaries were studied.
This study shows that the relationship between Jefferson and Burr was one of political expediency and that Jefferson's antipathy toward Burr began in 1791 and not as a result of the House presidential election of 1801. The thesis concludes that Jefferson used Burr's political influence in New England to achieve Democratic -Republican control of the federal government and then used the alleged conspiracy between Burr and the Federalists during the House election of 1801 as an excuse to begin Burr's political destruction.
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[en] THE EMERGENCE OF THE REAL IN THEATRICAL EXPERIENCE / [pt] A EMERGÊNCIA DO REAL NA EXPERIÊNCIA TEATRALBRUNO SANTOS AUGUSTO 27 March 2019 (has links)
[pt] A dissertação A emergência do real na experiência teatral oferece uma reflexão crítica do espetáculo Nu de Mim Mesmo, encenado no Rio de Janeiro em 2008 pela Companhia Teatro Autônomo, que representa um inovador espaço de experimentação no panorama teatral carioca dos últimos vinte anos. Criada em processo colaborativo entre os atores e a direção de Jefferson Miranda em parceria com Flavio Graff, a obra dialoga com Literatura, Artes Plásticas e Cinema, tendo como palco a cena teatral em sua materialidade específica. Realizando uma investigação de teor metadiscursivo, o grupo se insere em um viés do teatro contemporâneo que busca interrogar-se acerca de seus limites, oferecendo um campo experimental profícuo para o entrecruzamento de diversas mídias. Privilegiando uma perspectiva construtivista, a dissertação ensaia formas alternativas de compreensão do teatro contemporâneo, apontando para uma reflexão acerca de conceitos tais como realidade, sentido e identidade, entendidos para além das dicotomias real/ficcional. / [en] The master thesis The Emergence of the Real in Theatrical Experience offers a critical view on the play Nu de mim mesmo (Nude of myself) staged in Rio de Janeiro, in 2008, by the Companhia Teatro Autônomo (Autonomous Theatre Company) which represents an innovative reference in the Carioca theatre scenery of the past twenty years. Created in a collaborative process involving actors and the direction of Jefferson Miranda, in partnership with Flavio Graff, this production, based on the theatrical field in its specificity and materiality, also establishes dialogues with the fields of Literature, Fine Arts and Cinema. Throughout a metalinguistic driven investigation, the group can be inserted into a particular branch of the contemporary theatre that questions its own limits, offering an advantageous experimental field to the intercrossing of various medias. Within this scope, with an approach that is close to the constructivist perspective, the thesis rehearses alternative forms of understanding contemporary theatre, and analyzes concepts such as reality, meaning and identity, all of them understood beyond the reality/fiction dichotomy.
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Our Anglo-Saxon ancestors : Thomas Jefferson and the role of English history in the building of the American nationWalker, Jessica Lorraine January 2007 (has links)
This thesis contends that Anglo-Saxon studies made a powerful contribution to Thomas Jefferson's development of public concepts of American identity and nationalism in ways that have been elided by scholars preoccupied with Jefferson's classicism. Jefferson's comprehensive survey of Anglo-Saxon grammar, language, law and emigration provided him with a precedent for revolution and helped him develop a model of American nationhood. Jefferson's detailed study of the Anglo-Saxon era set him apart from writers on both sides of the Atlantic in the period 1750-1860, and this thesis will argue that to generalize his interest as 'whig history' or a subscription to a theory of Teutonic superiority is unjustified. Chapter One considers Jefferson's educational background, his exposure to Anglo-Saxon history and the degree to which he might have been encouraged to pursue it. Previous studies of Jefferson's Anglo-Saxonism have presumed that there was a 'Gothic font' from which American Founding Fathers could drink; the detailed study of Anglo-Saxon historiography in this chapter will show otherwise. Chapter Two is concerned with a detailed examination of the collections of books relating to Anglo-Saxon history and language that Jefferson collected throughout his lifetime. If Jefferson was concerned with whig dialogues, or interested in the Saxons as a product of a passion for Tacitus we should find evidence of it here. In fact, the study of Jefferson's library in Chapter Two demonstrates that Jefferson was genuinely an expert Anglo-Saxon scholar and regarded that knowledge base as a political tool. Chapters Three and Four constitute detailed examinations of the nationalist use to which Jefferson put his understanding of early English history. Chapter Three considers the problem of shared heritage with Britain confronting the American statesman in the 1760s and 1770s and his employment of pre-Norman history in resolving this conflict. Chapter Four enlarges upon the study of American national identity, with specific reference to the linguistic debates following on the Revolution. This chapter revolves around a reconsideration of Jefferson's Anglo-Saxon Essay and his attempts to introduce this language into the education of future American statesmen. Jefferson's examination of Anglo-Saxon history, when considered in this light, seems oddly discordant with the simplistic notion of Jefferson as a founder of Teutonic superiority. Chapter Five is interested in Jefferson's impact on historical rhetoric in the nineteenth century. Thomas Jefferson used English history as an aid to separating an American nation from the British Empire and he believed that Americans could look to their Anglo-Saxon ancestors for a precedent that would justify their independence from Britain. He saw in Anglo-Saxon studies a means for appropriating those parts of English history that could underpin a national identity defined by freedom, initiative, and perhaps a racial predilection for democracy, while simultaneously rejecting Britain's authority in his present.
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Quark Fragmentation and Hadron Formation in Nuclear Matter / Fragmentation des Quarks et Formation des Hadrons dans la Matière NucléaireDupré, Raphaël 09 November 2011 (has links)
La formation des hadrons est, dans le cadre de la théorie quantique de couleur (QCD), un processus non-perturbatif ; cette caractéristique entraîne d’importantes difficultés théoriques. C’est pourquoi, les mesures expérimentales de fragmentation dans différents noyaux sont une nécessité afin d’obtenir des progrès tangibles dans la compréhension des mécanismes de formation des hadrons. La thèse commence par les bases théoriques nécessaires à une telle approche, suivies des principaux modèles qui lui sont associés.La thèse se poursuit par l’analyse de données de Jefferson Lab obtenues à l’aide d’un faisceau d’électrons de 5 GeV incident sur différentes cibles (2H, C, Al, Fe, Sn et Pb). Les produits de la réaction sont mesurés avec le spectromètre CLAS. Les principaux résultats de cette expérience sont : (a) l’analyse multi-dimensionnelle des observables mesurées, qui permet une meilleure confrontation avec les modèles théoriques et l’extraction d’informations temporelles sur la fragmentation, et (b) l’observation d’une atténuation hadronique non-linéaire en fonction du rayon du noyau cible. Dans une partie plus théorique, le générateur d’événements PyQM, développé dans le but de reproduire les données de la collaboration HERMES, est présenté. Les résultats sont mitigés, en effet la base théorique utilisée ne semble pas s’appliquer au cas étudié, néanmoins certaines caractéristiques des données sont reproduites permettant de comprendre leurs origines parfois inattendues. Enfin, les possibilités d’expériences futures, à Jefferson Lab et dans un collisionneur ion-électron (EIC), sont explorées. / The hadron formation is, in the framework of the quantum chromodynamics theory (QCD), a non-perturbative process; this characteristic leads to important theoretical challenges. This is why experimental measurements of fragmentation in nuclei are a necessity in order to obtain substantial progress in our understanding of the mechanisms of hadron formation. The thesis begins with the introduction of theoretical background, followed by an overview of theoretical models. The thesis continues with the analysis of Jefferson Lab data obtained with a 5 GeV electron beam incident on various targets (2H, C, Al, Fe, Sn and Pb). The reaction products are measured with the CLAS spectrometer of Hall B. The main results are: (a) a multi-dimensional analysis of the measured observables, which permits a better confrontation with theoretical models and the extraction of temporal information on fragmentation, and (b) the observation of a non linear hadronic attenuation as a function of the target’s nuclear radius. The PyQM event generator, developed to reproduce the data from the HERMES collaboration, is also presented. The results are ambivalent, the theoretical basis used does not seem to apply to the studied case, however, some characteristics of the data are reproduced allowing to understand their origin, which is sometimes unexpected. Finally, the possibilities for future experiments, at Jefferson Lab and at an Electron-Ion Collider (EIC), are explored.
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Study of Generalized Parton Distributions and Deeply Virtual Compton Scattering on the nucleon with the CLAS and CLAS12 detectors at the Jefferson Laboratory (Virginia, USA) / Etude des Distributions de Partons Généralisées et de la Diffusion Compton Profondément Virtuelle sur le nucléon avec les détecteurs CLAS et CLAS12 au laboratoire Jefferson (Virginie, USA)Guegan, Baptiste 27 November 2012 (has links)
Les distributions de Partons Généralisées (GPDs) fournissent une nouvelle description de la structure du nucléon en termes de ses constituants élémentaires, les quarks et les gluons. Les GPDs donnent accès à une image unifiée du nucléon, corrélant l'information obtenu par les mesures des Facteurs de Forme et des Distributions de Parton. Elles décrivent la corrélation entre la position transverse et la fraction d'impulsion longitudinale des partons dans le nucléon.La Diffusion Compton Profondément Virtuelle (DVCS), ou l'électroproduction d'un photon réel sur un quark du nucléon eN -> e’N’γ , est le processus exclusif le plus direct pour accéder aux GPDs.Une expérience dédiée à l'étude du DVCS avec le détecteur CLAS du laboratoire Jefferson a été réalisé en utilisant un faisceau d'électron polarisé et une cible d'hydrogène non polarisée. Cette expérience a permis de collecter des événements DVCS sur le plus large espace cinématique jamais exploré dans la région de valence: 1 < Q^2 < 4.6 〖GeV〗^2, 0.1 < x_B < 0.58, 0.09 < -t < 3 〖GeV〗^2 .Dans ce travail, nous présentons l'extraction de trois observables DVCS différents: la section efficace non polarisée, la différence de section efficace polarisée et l'asymétrie de faisceau. Nous comparons nos résultats à un model de GPD. Nous présentons une extraction préliminaire des GPDs utilisant la dernière procédure d'ajustement aux données, et une interprétation préliminaire des résultats en termes de densité de parton. / The Generalized Parton Distributions (GPDs) provide a new description of the nucleon structure in terms of its elementary constituents, the quarks and the gluons. The GPDs give access to a unified picture of the nucleon, correlating the information obtained from the measurements of the Form Factors and the Parton Distribution Functions. They describe the correlation between the transverse position and the longitudinal momentum fraction of the partons in the nucleon.Deeply Virtual Compton Scattering (DVCS), the electroproduction of a real photon on a single quark of the nucleon eN -> e’N’γ, is the most straightforward exclusive process allowing access to the GPDs. A dedicated experiment to study DVCS with the CLAS detector of Jefferson Lab has been carried out using a 5.883 GeV polarized electron beam and an unpolarized hydrogen target, allowing to collect DVCS events in the widest kinematic range ever explored in the valence region : 1 < Q^2 < 4.6 〖GeV〗^2, 0.1 < x_B < 0.58, 0.09 < -t < 3 〖GeV〗^2 .In this work, we present the extraction of three different DVCS observables: the unpolarized cross section, the difference of polarized cross sections and the beam spin asymmetry. We present comparisons with GPD model. We show a preliminary extraction of the GPDs using the latest fitting code procedure on our data, and a preliminary interpretation of the results in terms of parton density.
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Mesure de la section efficace de l'électroproduction de photons à JLAB dans le but d'effectuer une Séparation Rosenbluth de la contribution DVCS / Measurement of the photon electroproduction cross section at JLAB with the goal of performing a Rosenbluth separation of the DVCS contributionMartí Jiménez-Argüello, Alejandro Miguel 11 July 2014 (has links)
L'étude de la structure interne des hadrons nous permet de comprendre la nature des interactions entre les partons, les quarks et les gluons, décrites par la Chromodynamique Quantique. Les processus de diffusion élastique, qui ont été utilisés avec succès pour mesurer les facteurs de forme des nucléons, sont inclus dans ce cadre. Les processus inélastiques sont également inclus dans ce cadre, ils nous permettent d'extraire beaucoup d'information grâce au développement des distributions de partons (PDFs). Par conséquent, tandis que la diffusion élastique d'électrons par le nucléon nous fournit des informations sur la répartition des charges, et donc de la distribution spatiale des composants du nucléon, la diffusion inélastique présente des informations sur la distribution d'impulsions au moyen des PDFs. Cependant, dans les processus inélastiques, il est possible d'étudier les processus exclusifs tels que la Diffusion Compton Profondément Virtuelle (DVCS), qui nous permet d'accéder aux distributions spatiale et d'impulsions des quarks simultanément. Ceci est possible grâce aux fonctions généralisées des distributions de partons (GPDS), qui nous permettent de corréler les deux types de distributions. Le processus connu sous le nom DVCS est le moyen le plus facile pour accéder aux GPDS. Ce procédé implique la diffusion d'un électron par un proton, au moyen de l'échange d'un photon virtuel, qui entraîne la diffusion des particules initiales et l'émission d'un photon réel. Ce processus est en concurrence avec le processus dit Bethe-Heitler, dans lequel le photon réel est émis par l'électron initial ou final. En raison de la faible section efficace de ce type de procédé, de l'ordre du nb, il est nécessaire d'utiliser une installation capable de fournir une haute luminosité pour réaliser les expériences. L'une de ces installations est le Thomas Jefferson National Accelerator Facility, où l'expérience appelée “Complete Separation of Virtual Photon and π⁰ Electroproduction Observables of Unpolarized Proton” a été réalisée au cours de la période entre Octobre et Décembre de 2010. Le principal objectif de cette expérience est la séparation de la contribution du terme provenant du DVCS à partir du terme d'interférence, résultant de la contribution du BH. Cette séparation est appelée “Séparation Rosenbluth”. Cette thèse porte sur le calorimètre électromagnétique qui a été utilisé pour détecter le photon dans l'expérience E07-007 à Jefferson Lab. Il y a aussi une introduction théorique à l'étude de la structure du nucléon, en révisant les concepts de facteurs de forme et des distributions de partons à travers des processus élastiques et inélastiques. Le calcul de la section efficace de la leptoproduction de photons est décrite en détail, ainsi que les buts de l'expérience E07-007. Dans cette thèse on décrit l'analyse des données enregistrées par le calorimètre électromagnétique, avec le but d'obtenir les variables cinématiques des photons réels résultants des réactions DVCS. Finalement, on décrit la sélection des événements à partir des données stockées, les réductions appliquées aux variables cinématiques et la soustraction de fond. En outre, le processus d'extraction des observables nécessaires pour le calcul de la section efficace de la leptoproduction de photons est décrite, ainsi que les principales étapes suivies pour effectuer la simulation Monte-Carlo utilisée dans ce calcul. Les sections efficaces obtenues sont indiquées à la fin de cette thèse. / The study of the inner structure of hadrons allows us to understand the nature of the interactions between partons, quarks and gluons, described by Quantum Chromodynamics. The elastic scattering reactions, which have been studied in order to measure the nucleon form factors, are included in this frame. The inelastic scattering reactions are also included in this frame, they allow us to obtain information about the nucleon structure thanks to the development of the parton distribution functions (PDFs). While through elastic scattering we can obtain information about the charge distribution of the nucleon, and hence, about the spatial distribution of the partons, through inelastic scattering we obtain information about the momentum distributions of partons, by employing the PDFs. However, we can study the exclusive inelastic scattering reactions, such as the Deeply Virtual Compton Scattering (DVCS), wich allow us to access to the spatial and momentum distributions simultaneously. This is possible thanks to the generalized parton distributions (GPDs), which allow us to correlate both types of distributions. The process known as DVCS is the easiest way to access the GPDs. This process can be expressed as the scattering of an electron by a proton by means of a virtual photon with the result of the scattered initial particles plus a real photon. We find a process competing with DVCS known as Bethe-Heitler (BH), in which the real photon is radiated by the lepton rather than the quark. Due to the small cross section of DVCS, of the order of nb, in order to conduct these kind of experiments it is necessary to make use of facilities capable of providing high beam intensities. One of these facilities is the Thomas Jefferson National Accelerator Facility , where the experiment JLab E07-007, “Complete Separation of Virtual Photon and π⁰ Electroproduction Observables of Unpolarized Protons”, took place during the months of October to December of 2010. The main goal of this experiment is the isolation of the contribution from the term coming form the DVCS from the interference term, resulting from the BH contribution. This isolation is known as “Rosenbluth Separation”. The work presented in this thesis focuses on the analysis of the data stored by the electromagnetic calorimeter, employed for the detection of real photons. There is also a a theoretical introduction to the study of the nucleon structure, reviewing the concepts of form factors and parton distributions through elastic and inelastic processes. The computation of the photon leptoproduction cross section is described in detail, as well as the goals of experiment E07-007. This thesis also describes the analysis of the data stored by the electromagnetic calorimeter, with the purpose of obtaining the kinematic variables of the real photons resulting from DVCS reactions. Finally, it describes the selection of events from stored data, the applied cuts to kinematical variables and the background subtraction. Also, the process of extraction of the necessary observables for computing the photon leptoproduction cross section is described, along with the main steps followed to perform the Monte Carlo simulation used in this computation. The resulting cross sections are shown at the end of this thesis.
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Deeply virtual Compton scattering at Jefferson Lab / Diffusion Compton profondément virtuelle au Jefferson laboratoryGeorges, Frédéric 25 October 2018 (has links)
Introduites au milieu des années 90, les Distributions Généralisées de Partons (GPD) sont aujourd'hui un élément clé dans l'étude de la structure interne du nucléon. Les GPD sont la généralisation des Facteurs de Forme et des Fonctions de Distribution de Partons. Elles englobent la distribution spatiale et la distribution en impulsion des partons à l'intérieur du nucléon, ce qui permet d'en effectuer une tomographie en trois dimensions. De plus, elles permettent d'obtenir le moment orbital angulaire total des quarks grâce à la règle de somme de Ji, ce qui est un élément crucial dans l'élucidation de l'énigme de la structure en spin du nucléon. En décrivant de manière plus complète la structure des hadrons en termes de quarks et gluons, il est possible d'approfondir notre compréhension de la Chromodynamique Quantique. Les GPD sont accessibles expérimentalement à travers les processus d'électro-production exclusifs profonds, et l'un des canaux les plus simples est la Diffusion Compton Profondément Virtuelle (DVCS). Un programme expérimental mondial a été lancé au début des années 2000 afin d'extraire ces GPD. L'expérience DVCS E12-06-114 qui a été effectuée dans le Hall A du Jefferson Laboratory (Virginie, Etats-Unis) entre 2014 et 2016 est incluse dans ce programme. Le but de cette expérience est de mesurer avec grande précision la section efficace DVCS dépendante de l'hélicité en fonction du transfert d'impulsion Q², pour des valeurs fixes de la variable de Bjorken xBj, sur une cible de proton. La récente amélioration à 12 GeV de l'accélérateur permet d'obtenir un bras de levier en Q² plus important que lors des expériences précédentes et de sonder des régions cinématiques encore inexplorées, tandis que le faisceau polarisé d'électrons permet de séparer les contributions des parties réelles et imaginaires de l'amplitude DVCS à la section efficace totale. Dans ce document, un bref résumé du programme expérimental mondial sur l'étude des GPD va être fourni, suivi par la description de l'appareillage et l'analyse des données de l'expérience E12-06-114. Enfin, les résultats des mesures de sections efficaces polarisées et non-polarisées sont présentés et comparés à une sélection de modèles. / Introduced in the mid 90’s, Generalized Parton Distributions (GPDs) are now a key element in the study of the nucleon internal structure. GPDs are a generalization of Form Factors and Parton Distribution Functions. They encapsulate both spatial and momentum distributions of partons inside a nucleon, allowing to perform its three-dimensional tomography. Furthermore, they allow to derive the total orbital angular momentum of quarks through the Ji sum rule, which is a crucial point to unravel the nucleon spin structure. By providing a more complete description of hadrons in terms of quarks and gluons, a deeper understanding of Quantum Chromodynamics can be reached.GPDs are experimentally accessible through deeply exclusive electro-production processes, and one of the simplest channels available is Deeply Virtual Compton Scattering (DVCS). A worldwide experimental program was started in the early 2000’s to extract these GPDs. The DVCS experiment E12-06-114 performed at Jefferson Laboratory Hall A (Virginia, USA) between 2014 and 2016, is encompassed in this program. The aim of this experiment is to extract with high precision the DVCS helicity-dependent cross sections as a function of the momentum transfer Q², for fixed values of the Bjorken variable xBj, on a proton target. The recent upgrade of the accelerator facility to 12 GeV allows to cover a larger Q² range than in previous measurements and probe yet unexplored kinematic regions, while the polarized electron beam allows the separation of the contributions from the real and imaginary parts of the DVCS amplitude to the total cross section. In this document, a brief summary of the worldwide experimental program for the study of GPDs will be provided, followed by a description of the E12-06-114 apparatus and data analysis. Finally, the results of the unpolarized and polarized cross-section measurements are presented and compared to a few selected models.
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