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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Spectroscopy of Electroproduced Light to Medium Mass Lambda Hypernuclei

Baturin, Pavlo 13 July 2010 (has links)
The E01-011 experiment at Jefferson Laboratory (JLab) studied light-to-medium mass Lambda hypernuclei via the (e,e'K+) electroproduction reaction. Precise measurement of hypernuclear ground state masses and excitation energies provides information about the nature of hyperon-nucleon interactions. Until recently, hypernuclei were studied at accelerator facilities with intense pi+ and K- meson beams. The poor quality of these beams limited the resolution of the hypernuclear excitation energy spectra to about 1.5 MeV (FWHM). This resolution is not sufficient for resolving the rich structure observed in the excitation spectra. By using a high quality electron beam and employing a new high resolution spectrometer system, this study aims to improve the resolution to a few hundred keV with an absolute precision of about 100 keV for excitation energies. In this work the high-resolution excitation spectra of 12B-Lambda, 7He-Lambda, and 28Al-Lambda hypernuclei are presented. In an attempt to emphasize the presence of the core-excited states we introduced a novel likelihood approach to particle identification (PID) to serve as an alternative to the commonly used standard hard-cut PID. The new method resulted in almost identical missing mass spectra as obtained by the standard approach. An energy resolution of approximately 400-500 keV (FWHM) has been achieved, an unprecedented value in hypernuclear reaction spectroscopy. For 12B-Lambda the core-excited configuration has been clearly observed with significant statistics. The embedded Lambda hyperon increases the excitation energies of the 11B nuclear core by 0.5-1 MeV. The 7He-Lambda spectrum has been observed with significant statistics for the first time. The ground state is bound deeper by roughly 400 keV than currently predicted by theory. Indication for the core-excited doublet, which is unbound in the core itself, is observed. The measurement of 28Al-Lambda provides the first study of a d-shell hypernucleus with sub-MeV resolution. Discrepancies of up to 2 MeV between measured and theoretically predicted binding energies are found. Similar disagreement exists when comparing to the 28Si-Lambda mirror hypernucleus. Also the core-excited structure observed between the major s-, p- and d-shell Lambda orbits is not consistent with the available theoretical calculations. In conclusion, the discrepancies found in this study will provide valuable input for the further development of theoretical models.
12

Multiplicities of hadrons in deep-inelastic scattering of muons on nucleons at COMPASS / Multiplicités de hadrons en diffusion inélastique profonde de muons sur nucléons à COMPASS

Pierre, Nicolas 03 July 2019 (has links)
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.
13

Differential cross section measurement and phase shift analysis for Σ⁺p elastic scattering / Σ⁺p弾性散乱の微分断面積測定および位相差解析

Nanamura, Takuya 23 March 2023 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24408号 / 理博第4907号 / 新制||理||1701(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 永江 知文, 准教授 成木 恵, 教授 橋本 幸士 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
14

The Strange Presence: the Series of Art Practices on the Strangeness, the Familiar and the Presence.

Jeon, Hye Jeon January 2020 (has links)
No description available.
15

K<sup>*0</sup> Photoproduction and Electroproduction Measured at CLAS

Hleiqawi, Ishaq Hasan 26 April 2006 (has links)
No description available.
16

Search for the nnΛ state via the ³H(e,e’K⁺)X reaction at JLab / JLabにおける³H(e, e’K⁺)X反応を用いたnnΛ状態の探索

Suzuki, Kazuki 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第23701号 / 理博第4791号 / 新制||理||1686(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 永江 知文, 准教授 成木 恵, 教授 中家 剛 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
17

Untersuchungen zu den Reaktionen pp--&amp;gt;nK+Sigma+ und pp--&amp;gt;pK0Sigma+

Karsch, Leonhard 21 June 2005 (has links)
Das Kuehlersynchrotron COSY im Forschungszentrum Juelich kann u.a. einen guten Protonenstrahl fuer Experimente zur Verfuegung stellen. An einem der Experimentierplaetze steht das Flugzeitspektrometer COSY-TOF. Es eignet sich hervorragend zur Untersuchung von Reaktionen, bei denen wenige Teilchen enstehen. Solange die entstehenden Teilchen einen Winkel von hoechstens 70 Grad mit Strahlachse einschliessen, werden diese nachgewiesen. Damit sind im schwellennahen Energiebereich die Flugzeit und Flugrichtung aller langlebigen Teilchen bestimmbar. Zum Nachweis kurzlebiger Teilchen gibt es einige Module im Flugzeitspektrometer zur Rekonstruktion der Flugrichtung. Die Arbeit untersucht zwei Reaktionen, bei denen Hyperonen entstehen: pp--&amp;gt;nK+Sigma+ und pp--&amp;gt; pK0Sigma+ bei einem Strahlimpuls von 2,95 GeV/c. Im schwellennahen Energiebereich liegen bisher keine (in Zeitschriften) veroeffentlichten Daten vor. Die Kenntnis der Reaktionsmechanismen sind jedoch wuenschenswert, um die physikalsiche Beschreibung in vielen Bereichen zu verbessern. Dazu gehoeren die Eigenschaften der Teilchen (Strangenessgehalt des Nukleons) und die Wechselwirkungen zwischen den Teilchen (auch in extrem dichter Materie). In dieser Arbeit werden die zur Kalibrierung des Detektors notwendigen Schritte, die vom Autor durchgefuehrt wurden, erlaeutert. Im Anschluss wird die Analyse der Daten fuer ein Experiment ausfuehrlich vorgestellt. Durch einige Bedingungen wird erreicht, dass eine (nahezu) untergrundfreie Menge der gesuchten Ereignissen vorliegt. Die Anzahl der gefundenen Ereignisse laesst fuer die Reaktion pp--&amp;gt; nK+Sigma+ nur die Angabe eines totalen Wirkungsquerschnittes zu. Fuer die Reaktion pp--&amp;gt; pK0Sigma+ wird ebenfalls der totale Wirkungsquerschnitt bestimmt. Weiterhin werden Untersuchungen zum Reaktionsmechanismus durchgefuehrt. Dadurch wird ersichtlich, dass diese Reaktion einen starken resonanten Anteil im K0Sigma-System hat. Die Analyse wird auch auf zwei andere Experimente mit COSY-TOF angewendet. Das Auftreten hoeherer Drehimpulse ist erst bei groesseren Strahlimpulsen 3,2 GeV/c zu erkennen.
18

Leituras do grotesco em sete narrativas setsuwa de Konjaku Monogatarishû / Reading the grotesque in seven setsuwa tales from Konjaku Monogatarishû

Ramos, Vinicius Ito 27 November 2017 (has links)
O presente trabalho propõe uma análise centrada em sete narrativas de cunho secular da seção japonesa contidas na coletânea de narrativas setsuwa denominada Konjaku Monogatarishû do século XIII. As narrativas serão traduzidas para o vernáculo e analisadas pelo viés do corpo grotesco em suas mais diferentes manifestações, assim como explicitado por Bakhtin (2013) e pelo viés do estranhamento tal qual formulado por Wolfgang Kayser (1986). Devido ao fato de as narrativas setsuwa possuírem padrões contrastantes da estética literária e temas vigentes na era Heian, identificou-se a importância do estudo das mesmas pelo viés do grotesco como uma leitura de rompimento com o ideal estético literário, pautando-se pela descrição explícita dos fatos, personagens e ações cotidianas. / The present work aims to analyses seven Japanese secular setsuwa tales included on Konjaku Monogatarishû compilation. The narratives will be translated to nowadays language and analyzed by many points fo view, as studied by grotesque body and others manifestations on Mikhail Bakhtin (2013) theory and by the theory of strangeness by Kayser (1986). Due to the fact that setsuwa tales has different patterns of literary aesthetics and themes in Heian period, the importance of this study by the grotesque as a rupture on literary aesthetics was identified also, because of the approximated description of the facts, figures and the daily actions.
19

Estudo da produção de estranheza em colisões entre íons pesados relativísticos a & / Measurements of Strangeness Production at 62.4 GeV

Guimarães, Karin Silvia Franzoni Fornazier 28 September 2007 (has links)
O principal objetivo deste trabalho foi obter a produção das partículas estranhas K0, e em colisões entre íons pesados relativísticos para ÖsNN = 62.4 GeV, bem como estudar o comportamento sistemático dessa produção em função da energia. Para isso, utilizamos os dados provenientes da colisão de íons pesados relativísticos obtidos pelo experimento STAR do RHIC. O objetivo deste trabalho também foi o de estudar dois estágios específicos da evolução do fireball formado nessas colisões: os chamados freeze-out químico e térmico. Estes estágios (ou fases) foram estudadas a partir das razões entre diversas partículas e da distribuição de momento transversal das mesmas, comparando os resultados com previsões e ajustes de modelos térmicos, a fim de avaliar possíveis efeitos da formação de um Plasma de Quarks e Gluons (QGP) em equilíbrio térmico sobre os hádrons medidos pelo experimento. O freeze-out químico foi estudado a partir das razões entre abundâncias de partículas produzidas na colisão, que foram comparadas a ajustes de um modelo térmico que trata o fireball como um gás de hádrons em equilíbrio (THERMUS) e aos resultados de um modelo que não assume esse equilíbrio (SHM). Com essa abordagem, verificamos que o modelo THERMUS ajusta bem os dados experimentais para uma ampla faixa de energias de colisão, principalmente para 62.4 GeV. Os parâmetros termodinâmicos obtidos foram estudados em função da energia para verificarmos se há um comportamento suave do sistema ou mudanças abruptas. O estudo indicou que esse comportamento é suave com a energia. Ainda neste estudo do freeze-out químico, comparamos os resultados do modelo THERMUS com os resultados do modelo que considera o não ? equilíbrio químico, o SHM. Nesta comparação, a razão apresentou um comportamento interessante, sugerindo que a energias mais baixas o sistema se comporta conforme a prescrição do modelo SHM, enquanto que o modelo que considera o fireball como um gás de hádrons em equilíbrio, novamente, demonstrou melhor compatibilidade a energias mais altas, reafirmando aqui a indicação de uma possível formação de um sistema termalizado. O freeze-out cinético/térmico foi estudado com os espectros de momento transversal, considerando um modelo fenomenológico inspirado na hidrodinâmica. Os resultados mostram que eventos mais centrais apresentam uma velocidade de expansão maior e uma temperatura menor, condizente com uma fonte que tem um gradiente de pressão maior. Também foi observado que a partícula ? apresenta sempre uma temperatura maior que as outras partículas (p, ?, ?) indicando um desacoplamento anterior dessas partículas em relação às outras. Finalmente, estudamos a utilização do SVT para a reconstrução de V0s, procurando compreender a maneira correta de se utilizar este detector na análise. Os resultados mostram que a utilização desse detector pode levar a uma melhora na eficiência e na pureza durante a reconstrução dessas partículas. / The main goal of this work was to measure the production of the singly strange particles, such as K0, and in Au+Au collisions at ?sNN = 62.4 GeV, inserting these results in a systematic energy scan study. The data were obtained from the STAR detector, one of the RHIC experiments. In addition, we have used the particle production in these collision to study two specific stages of the fireball evolution: the chemical and kinetic freeze-outs. These two stages were studied comparing the ratio between different particles (strange or not) and also the transverse momentum distribution with thermal models fits in order to check possible effects of equilibrated Quark Gluon Plasma (QGP) in the hadron production. The chemical freeze-out was studied comparing the ratios between particles produced in the collision with two different thermal models: one which assumes a equilibrated hadron gas (THERMUS) and another one which assumes a possible non-equilibrated system (SHM). The experimental data were well described by the THERMUS model fit in a great range of energy collisions, mainly at 62.4 GeV. The thermodynamic parameters had been studied as function of the energy in order to verify if it has a smooth or abrupt behavior. The result indicated that this behavior is very smooth with energy. We also compared these results with SHM\'s predictions and, in this comparison, the ratio presented an interesting behavior, suggesting that at low energies the fireball consists of a non-equilibrated system, such as described by SHM model, whereas the model that considers the fireball as a equilibrated hadron gas. The kinetic freeze-out was studied with the transverse momentum spectra using a hydrodynamics inspired model. The results indicate that for the most central events there is a higher expanding velocity and a lower freeze-out temperature. It was also observed that for the particle, the freeze-out temperature is higher than the one for other particles (?, K, p) indicating an earlier decoupling of these particles from the fireball. Finally, we have studied the inclusion for the SVT in the V0 reconstruction analysis, trying to optimize this detector usage in the analysis. The results show that the inclusion of this detector in the analysis can improve the efficiency and purity of the V0 reconstruction in the STAR experiment.
20

Interjeições de assombro e de estranheza no português paulistano e macaense: um contexto pragmático e de afetividade / Interjections of astonishment and strangeness in Paulistano and Macanese Portuguese: a pragmatic and affective context

Guerra, Alexandre Yuri Ribeiro 22 June 2017 (has links)
Este trabalho apresenta um estudo sobre interjeições em viés funcionalista através de uma análise comparativa dos usos linguísticos de expressões de assombro e de estranheza do português paulistano em relação ao português macaense. A decisão teórico-metodológica ampara-se na Linguística Centrada no Uso, na linha cognitivo-funcional, estudada por meio das obras de Heine, Claudi e Hünnemeyer (1991), Tomasello (2003), Gonçalves, Lima-Hernandes e Casseb-Galvão (2007), Givón (2009), dentre outros autores. Este campo teórico tem como âmago a preocupação em lidar com dados que preservem os contextos de produção de uso. Distinguir entre expressões de assombro e de estranheza não é uma tarefa fácil nem em dicionários e nem em gramáticas. É até mesmo impossível, atualmente, afirmar com certeza tal distinção pela ausência de investigação mais a fundo da pragmática e dos processamentos mentais envolvidos em conjunto com as produções linguísticas. O objetivo geral do estudo é o de introduzir uma nova pesquisa sobre interjeições ao verificar se existem diferenças nos usos de expressões interjetivas entre as duas variedades investigadas, indagando a questão da marginalidade dessa classe de palavras entre gramáticos e linguistas. Os dados para a investigação partiram de dois materiais. O primeiro corpus é constituído por registros audiovisuais oriundos de filmes paulistanos coletados por Guerra (2011) e de inquéritos realizados por Lima-Hernandes et alii (2012) e Rodrigues (2013). As expressões interjetivas presentes nestes materiais são comparadas com um segundo corpus composto por usos linguísticos manifestados por macaenses, falantes de língua materna cantonesa e portuguesa, registrados em gravações de teatro, conversas informais e entrevistas em programas televisivos e de rádio da península. Interjeições são preponderantemente de ordem pragmática, pois os seus significados derivam quase que exclusivamente da entonação do falante e do contexto em que se inserem. Apesar da pouca atenção recebida por gramáticos e linguistas, são estratégias comunicativas utilizadas fartamente em nosso cotidiano e, portanto, representam uma rica fonte de investigação. / This research presents a study on interjections in a functionalist perspective through a comparative analysis on language usages of astonishment and strangenesss expressions in Paulistano and Macanese Portuguese. The theoretical basis and methodological decision are sustained by the Usage-based Linguistics, in a cognitive functional bias, studied in the works of Heine, Claudi and Hünnemeyer (1991), Tomasello (2003), Gonçalves, Lima-Hernandes and Casseb-Galvão (2007), Givón (2009), among other authors. This theoretical field has as its core the concern to deal only with data that preserve the contexts of usage production. Distinguish expressions between astonishment and strangeness is not an easy task in dictionaries or even in grammar books. Currently, it is even impossible to claim for sure that these expressions have a distinction because of the absence of a deeper investigation, focused on pragmatics and mental processes involved jointly with linguistic productions. The general objective of this project is to introduce a new research on interjections, verifying if there are differences in usages of these expressions between the two language varieties investigated and to inquire about the marginalization of this word class by grammarians and linguists. Data utilized for investigation are originated from two materials. The first corpus is composed by audiovisual records derived of Paulistano movies compiled by Guerra (2011) and interviews made by Lima-Hernandes et alii (2012) and Rodrigues (2013). The interjective expressions observed will be compared with a second corpus composed by linguistic usages of Portuguese displayed by Macanese, speakers of Cantonese and Portuguese as mother languages, recorded in theater presentations, informal dialogues and interviews realized by TV and radio programs. Interjections have the pragmatic order as a predominant characteristic because their meanings derive almost exclusively from the intonation of the speaker and the context inserted. Despite of the minimal attention gave by grammarians and linguists, they are communicative strategies heavily utilized in our daily life and, consequently, are a rich source of investigation.

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