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Elastic scattering of polarized deuterons from aluminum, silicon, and nickelSchwandt, P. January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1967. / Vita. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Optical wave propagation in active mediaTaouk, Habib B. January 1991 (has links)
No description available.
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MAGNETIC FIELDS AND OTHER PHYSICAL CONDITIONS IN THE INTERSTELLAR MEDIUMKiuchi, Furea 01 January 2012 (has links)
This document consists of two very different projects but the common thread is in the interest of magnetic fields. It describes the effect of magnetic fields in two Interstellar Medium regions in the Galaxy. Electromagnetic force is one of the four fundamental forces in physics. It is not known where magnetic field has initially risen in the Universe, but what is certain is that it has significant effect in the dynamics of star formation and galaxy formation. The studies aim to better understand the effects of field in an active star forming region and in the halo of the Galaxy. We observed the HI 21 cm spectral line via the Zeeman effect in attempt to detect line-of-sight magnetic field strengths in both of the projects. For the star forming region project in Chapter 2, towards the Eagle Nebula, an upper limit of the field strength was determined. From the observational results, physical conditions of the region were modeled. For the second project in Chapter 3, we attempted to detect magnetic fields via Zeeman effect towards non galactic disk objects. All of the observed positions have radial velocities that cannot be explained by the simple galactic rotation. Hence, they are considered to be non galactic disk sources and often grouped as High Velocity Clouds. With a unique observational technique and analysis, we derived the best fit line-of-sight magnetic fields. A particular interest to us is the Smith Cloud. From the detection of magnetic field, we attempted to estimate the density of the ambient medium in the halo, which will be useful for studying the galaxy formation.
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A dinâmica socioespacial de Itapuranga no contexto da modernização e rede urbana / The socioespacial dynamics of Itapuranga in the context of modernization and urban networksCampos, Kátia Mesquita 25 January 2017 (has links)
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Previous issue date: 2017-01-25 / By means of the transformations unleashed by the process of modernization, the territories become integrated and fluid, giving rise to the current socio-spatial dynamics. This process allows the diffusion of the urban centers by the territory and its organization in urban networks that articulate and form the various existing centralities. Before that, this work has as an objective to understand the socio-spatial dynamic of Itapuranga by means of the relationships and interactions established between the municipality and the other centers of the urban network, boosted by the process of territorial modernization. For this, the methodological procedures of research were based on biographic review, data collection in public and private institutions, application of fieldwork, questionnaires and interviews. The present work revealed that the socio-spatial dynamic of a municipality forms by means of the relationships from this center with the others municipalities of the urban network, creating a structure and spatial organization capable of meeting the yearnings of the social relations of production. / Por meio das transformações desencadeadas pelo processo de modernização, os territórios se tornam integrados e fluídos, dando origem a atual dinâmica socioespacial. Esse processo permite a difusão dos centros urbanos pelo território e sua organização em redes urbanas, que se articulam e formam as várias centralidades existentes. Diante disso, este trabalho tem como objetivo compreender a dinâmica socioespacial de Itapuranga por meio dos relacionamentos e interações estabelecidos entre o município e os demais centros da rede urbana, dinamizados pelo processo de modernização territorial. Para isso, os procedimentos metodológicos da pesquisa foram baseados em revisão bibliográfica, levantamento de dados em instituições públicas e privadas, aplicação de trabalho de campo, questionários e entrevistas. O presente trabalho revelou que a dinâmica socioespacial de um município forma-se por meio dos relacionamentos desse centro com os demais municípios da rede urbana, criando uma estrutura e organização espacial capaz de atender aos anseios das relações sociais de produção.
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Top Quark Spin Correlations with the CMS DetectorJason R Thieman (15354421) 27 April 2023 (has links)
<p>This dissertation presents precision measurements of top quark polarizations and top quark pair spin correlations, which probe the independent coefficients of the top-spin components of the top quark pair production density matrix, targeting all channels (ee, eµ, µµ) of the top quark pair dileptonic decay mode with final states containing two oppositely charged leptons, and using 137.7 fb<strong>⁻¹</strong> of data recorded by the CMS experiment at the LHC with 13 TeV center-of-mass energy, during 2016, 2017, and 2018.</p>
<p>All measured observables are corrected for detector efficiencies, acceptances, and migrations, unfolded to parton-level, and extrapolated to the full phase space using a regularized unfolding procedure.</p>
<p>Spin-density coefficients are extracted from the unfolded distributions and compared to theoretical predictions and predictions from Monte Carlo simulations with next-to-leading-order matrix element accuracy interfaced with parton-shower algorithms.</p>
<p>The measurements are performed both in the full phase-space and differentially as a function of top quark pair invariant mass.</p>
<p>The measured coefficients showed decent agreement with the MC predictions, and better agreement when compared to QCD perturbative calculations for top quark pair production at NLO with electroweak corrections, and the measurement precision for one-dimensional normalized unfolded cross-sections and extracted coefficients were improved by as much as a factor of two compared to previous measurements.</p>
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Expression of SARS CoV2 receptors influenced upon Cytokine polarizations (IL-4 and IFNγ) in Hemangioendothelioma cellsKoopari, Chandra Lekha January 2022 (has links)
No description available.
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Application of the relativistic random-phase and distorted wave impulse approximations to quasielastic proton-nucleus scatteringVan Niekerk, David Douglas 12 1900 (has links)
Thesis (PhD (Physics))--University of Stelllenbosch, 2010. / ENGLISH ABSTRACT: In this dissertation a fully relativistic model for polarized inclusive quasielastic proton-nucleus
scattering is developed. Using a standard relativistic impulse approximation (RIA) treatment of
quasielastic scattering and a two-body SPVAT form of the current operator, it is shown how the
behaviour of projectile and target can be decoupled. Subsequently, different models for projectile
and target can be adopted and combined to examine a variety of relativistic effects.
The most simplistic model of the target is provided by a mean-field nuclear matter approximation
to the relativistic meson-nucleon model, quantum hadrodynamics (QHD). Here relativistic
effects manifest as an effective mass, which is lower than the free mass, of the constituent nucleons.
This model is improved upon by including many-body correlations through medium-modification
of meson propagators in the relativistic random-phase approximation (RPA).
Since it is generally accepted that the strong nuclear force and the extended range of the nuclear
potential lead to distortion effects on the projectile and ejectile (seen as a modulation of the wave
functions), our formalism is geared towards the use of relativistic distorted waves (RDWIA). The
distorted waves are written as partial wave expansions and are solutions to the Dirac equation with
potentials. The inclusion of distortions, however, greatly increases the computational burden and
we show how a number of analytical and numerical techniques can be used to facilitate the process
of calculation. It is also shown how the standard relativistic plane wave treatment (RPWIA) can,
instead, be easily employed to obtain a baseline for determining the impact of distortions.
A calculation is performed for the reaction 40Ca(!p, !p !) at a beam energy of 500 MeV. Here it is
found that the effect of correlations on the RPWIA calculation can be seen as a quenching of the
cross section that is expected to become more pronounced at lower energies or for higher density
targets. A RDWIA calculation shows additional reduction and if target correlations are included
this effect is enhanced. To our knowledge this is the first calculation that attempts to include both
these effects (RPA and RDWIA) in the context of quasielastic proton-nucleus scattering. / AFRIKAANSE OPSOMMING: In hierdie proefskrif word ’n ten volle relatiwistiese model vir die berekening van inklusiewe kwasielastiese
proton-kern verstrooiing daargestel. Deur gebruik te maak van ’n standaard relatiwistiese
impulsbenadering (RIA) vir kwasi-elastiese verstrooiing asook ’n twee-deeltjie-SPVAT-vorm vir die
stroom-operator, word daar gewys hoedat die gedrag van die projektiel en teiken ontkoppel kan
word. Verskillende modelle kan dus vir die projektiel en teiken gebruik word om ’n verskeidenheid
relatiwistiese effekte te bestudeer.
Die mees simplistiese model vir die teiken word verskaf deur ’n gemiddelde-veld kernmateriaalbenadering
tot die relatiwistiese meson-nukleon-model, kwantum-hadrodinamika (QHD). In hierdie
model manifesteer relatiwistiese effekte as ’n effektiewe massa, wat kleiner is as die vrye massa, van
nukleone in die kern. Hierdie model word verbeter deur die inagneming van veeldeeltjie korrelasies
deur medium-gewysigde meson-propagators in die relatiwistiese ewekansige-fase-benadering (RPA).
Aangesien dit algemeen aanvaar word dat die sterk-wisselwerking en die reikwydte van
die kernpotensiaal aanleiding gee tot vervormingseffekte op die projektiel en ejektiel (gesien
as die modulasie van golffunksies), is ons model optimaal geformuleer om gebruik te maak
van relatiwistiese vervormde golwe (RDWIA). Die vervormde golwe word geskryf as parsi¨elegolf
uitbreidings en dien as oplossings vir die Dirac-vergelyking met potensiale. Insluiting van
vervormings vermeerder egter die berekeningslas geweldig en ons toon hoedat ’n aantal analitiese en
numeriese tegnieke gebruik kan word om die proses te vergemaklik. Daar word ook aangetoon hoe
die standaard- relatiwistiese-vlakgolf-benadering (RPWIA), in plaas van vevormde golwe, maklik
gebruik kan word om ’n verwysingspunt vir die meting van die effek van vervormings te bepaal.
’n Berekening vir die reaksie 40Ca(!p, !p !) teen ’n projektiel-energie van 500 MeV word getoon.
Hier word dit gevind dat die effek van korrelasies op die RPWIA-berekening gesien kan word as
’n verlaging van die kansvlak. Daar word verwag dat hierdie effek duideliker sal word by laer
energie¨e en ho¨er kerndigthede. ’n RDWIA-berekening word getoon wat daarop dui dat addisionele
verlaging in die kansvlak voorkom en indien korrelasies hier ingesluit word, word hierdie effek
vergroot. Sover ons kennis strek, is hierdie die eerste berekening wat poog om beide hierdie effekte
(RPA en RDWIA) in die konteks van kwasi-elastiese proton-kern verstrooiing in te sluit.
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Caractéristiques spatiales et temporelles d'une tache focale LMJLe Cain, Aurélie 20 January 2012 (has links)
La performance des cibles du Laser LMJ est très sensible à l'uniformité de la tache focale du laser. La technique utilisée à ce jour pour éviter les inhomogénéités est de rendre le faisceau partiellement incohérent, ce qui a pour conséquence la fluctuation de points chauds (speckles) au cours du temps, avec un effet de moyenne. De nombreux travaux ont d'ores et déjà été menés concernant l'étude de ces points chauds dans le cadre d'un faisceau unique au plan focal. Dans cette thèse, on s'intéresse à ces points chauds lorsqu'il sont issus de la superposition de faisceaux multiples, et plus particulièrement aux points chauds dans le cas de la configuration du LMJ. On a établi une équation analytique permettant de calculer la taille des points chauds dans le cas d'un speckle généré par des faisceaux multiples. Cette formule est en parfait accord avec les différents résultats obtenus par simulations numériques grâce au code PARAX. On a ainsi pu prédire la taille du grain de speckle LMJ en fonction de différentes configurations LMJ telle qu'une configuration à deux ou trois cônes et pour des choix de polarisations différents. Il en ressort que l'impact de la polarisation est assez faible sur les caractéristiques du speckle LMJ. Toutefois la double polarisation est la plus adaptée aux critères d'uniformité requis pour une bonne interaction laser-plasma. D'autre part on a montré que les grains de speckle LMJ sont de l'ordre de la longueur d'onde.Dans la seconde partie de cette thèse, on a établi les formules des contraste, temps de vie, trajectoires et vitesses des points chauds deux techniques de lissage : Lissage par Dispersion Spectrale Transverse (LDST) et Longitudinal (LDSL). Ces derniers sont respectivement utilisés sur le NIF et prochainement sur le LMJ. On a ainsi montré que quels que soient le nombre de cône et le choix des polarisations faites sur le LMJ, la durée de vie d'un point chaud LMJ est environ de 2 ps et le contraste intégré sur des temps infinis est approximativement de 15%. Les vitesses sont également très faibles (10-6c) et faiblement influencées par le choix des polarisations. / The future French Laser Megajoule (LMJ) is a multiple laser beam facility built to achieve Inertial confinement Fusion (ICF). It is mainly designed for an indirect drive scheme using X-rays conversion. In this scheme, the target in the center of the hohlraum is irradiated and then compressed by the X-rays more uniformly than what it would be in a direct drive schemes. However, a high of uniformity is still needed to reach ignition since the propagation of intense laser beams in an under-critical plasma can generate laser-plasma instabilities (LPI). The control of LPI is of crucial importance for the success of ICF. By breaking both spatial and temporal coherences, the use of optical smoothing techniques, such as smoothing by spectral dispersion (SSD), often dramatically reduces LPI and also ensures the reproducibility of laser conditions from one shot to another. An accurate description of the speckle pattern in the hohlraum is thus of great interest for ICF experiments.We focus our attention on the spatial and then temporal properties of the speckles pattern generated by multiple laser beams. At first, we establish equations for the 3D speckle size based on autocorrelation functions. Numerical simulations of the propagation of multiple laser beams in vacuum are then performed with the PARAX code in configurations where the paraxial approximation can be used. The case of speckle patterns in the LMJ configuration in the zone where all the beams overlap is eventually studied. We show that such speckles have an ellipsoidal shape. Finally, influence of the polarization of the beams on the shape, size and abundance of the speckles is also investigated. In a second part we study the important aspect of temporal smoothing techniques like the movement of the speckles. This work is also triggered by the development of a statistical model that describes the motion of hot spots in order to evaluate the contrast, the trajectory and the velocity of LMJ hot spots. We address these quantities in the case of a speckle pattern generated by multiple laser beams thanks to the autocorrelation function in intensity.
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Properties of baryons in the chiral quark modelOhlsson, Tommy January 1997 (has links)
In this thesis, several properties of baryons are studied using the chiral quark model. The chiral quark model is a theory which can be used to describe low energy phenomena of baryons. In Paper 1, the chiral quark model is studied using wave functions with configuration mixing. This study is motivated by the fact that the chiral quark model cannot otherwise break the Coleman–Glashow sum-rule for the magnetic moments of the octet baryons, which is xperimentally broken by about ten standard deviations. Configuration mixing with quark-diquark components is also able to reproduce the octet baryon magnetic moments very accurately. In Paper 2, the chiral quark model is used to calculate the decuplet baryon magnetic moments. The values for the magnetic moments of the ++and− are in good agreement with the experimental results. The total quark spin polarizations are also calculated and are found to be significantly smaller than the non-relativistic quark model results. In Paper 3, the weak form factors for semileptonic octet baryon decays are studied in the chiral quark model. The “weak magnetism” form factors are found to be consistent with the conserved vector current (CVC) results and the induced pseudotensor form factors, which seem to be model independent, are small. The results obtained are in general agreement with experiments and are also compared with other model calculations. / QC 20100618
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Photoproduction of K<sup>*+</sup>¿¿/¿¿<sup>0</sup> and K<sup>0</sup>¿¿<sup>+</sup> from the Proton Using CLAS at Jefferson LabTang, Wei January 2012 (has links)
No description available.
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