The production of the neutral strange particles Λ, Λ[bar] and K⁰_s at HERA has been studied with the ZEUS detector, using an integrated luminosity of 121pb^-1 . Differential cross-sections are measured in a High Q² DIS sample (Q² ≥ 25GeV²), a Low Q² DIS sample (5 ≤ Q² ≤ 25GeV² ) and a photoproduction sample. The photoproduction sample has Q² <= 1GeV² and at least two jets that satisfy E_T^jet > 5GeV and |η^jet| < 2.4. Cross-sections are measured as a function of the particle P_T and η, and additionally as a function of the event Q² and x in the DIS samples, and as a function of x_γ in the photoproduction sample. The DIS cross-sections are compared to the ARIADNE Monte Carlo, which broadly describes the data. The photoproduction cross-sections are compared to PYTHIA, where the agreement is less good, particularly at low x_γ. The baryon-antibaryon asymmetry, defined as (Λ-Λ[bar])/(Λ+Λ[bar]), is measured and always found to be consistent with zero, indicating little transfer of the Baryon Number from the beam proton to the Λ system in the detector region. The polarization of Λ and Λ[bar] is measured and also found to be always consistent with zero, indicating that there is no preferred frame in Λ production. The baryon-meson ratio (Λ + Λ[bar])/K⁰_s is studied, and is found to generally agree with ARIADNE in DIS, but give an excess over PYTHIA in photoproduction. The excess is particularly prominent at low x_γ in events with no clear jet structure. This is interpreted as hadron production in this region depending on a more-than-one-dimensional overlap of quark wave functions. An excess of strangeness in this region at low x_γ with no high E_T jets would be significant. It is investigated by taking the ratio of strange particles to charged tracks but no excess is seen.

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 250-257). Available also in a digital version from Dissertation Abstracts.

Legends That Sleep Kick Bogotá at Night is a short story collection that parodies the gender, moral, and social constructs of Colombian mythology and folklore. Set in contemporary times, the stories depict slews of grotesque transformations and rituals happening during plane flights, sibling tomfoolery, neck kisses, social network log-ins, trips to the family graveyard, conversations with escorts, and waves of town gossip. The folktale monsters aim to enlist the reader as their accomplice in their quest to fight against the forces that seek to permanently subdue and marginalize them. / Includes bibliography. / Thesis (M.F.A.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

Title: Study of the rare B-meson decays with the ATLAS experiment Author: Marek Biroš Institute: Institute of Particle and Nuclear Physics Supervisor: RNDr. Pavel Řezníček, Ph.D., Institute of Particle and Nuclear Physics Abstract: The rare B0 d → K∗0 (892) μμ decay is one of the B-physics channels sensitive to Beyond Standard Model effects. The potential deviation from Standard Model predictions could be observed in the angular distribution of this decay. The work compiles several sub-tasks at the initial stage of this complex analysis: decay angles fit validation and signal event preselection. The fit functions used in the analysis are verified on generated toy Monte Carlo data. Ranges of parameters, for which are these functions positive, are established and within this parametric space, the testing of possible intrinsic fit biases is evaluated. A dependence of the fit bias with respect to the collected number of events (expected in Run 2 as well as at HL-LHC) and to the different signal-to- background ratio is studied. The second part of the thesis deals with processing of raw reconstructed data from the detector into n-tuples resulting in a more compact dataset that would be used in the final analysis. Within the process, baseline cuts are applied in order to minimize size of final datasets by reducing...

Cette thèse porte sur l'étude de modèles non linéaires issus de la mécanique quantique relativiste.Dans la première partie, nous démontrons à l'aide d'une méthode de tir l'existence d'une infinité de solutions d'équations de Dirac non linéaires provenant d'un modèle de hadrons et d'un modèle de la physique des noyaux.Dans la seconde partie, nous prouvons par des méthodes variationnelles l'existence d'un état fondamental et d'états excités pour deux modèles de la physique des hadrons. Par la suite, nous étudions la transition de phase reliant les deux modèles grâce à la Gamma-convergence.La dernière partie est consacrée à l'étude d'un autre modèle de hadrons dans lequel les fonctions d'onde des quarks sont parfaitement localisées. Nous énonçons quelques résultats préliminaires que nous avons obtenus. / This thesis is devoted to the study of nonlinear models from relativistic quantum mechanics.In the first part, we show thanks to a shooting method, the existence of infinitely many solutions of nonlinear Dirac equations of two models from the physics of hadrons and the physics of the nucleus.In the second part, we prove thanks to variational methods the existence of a ground state and excited states for two models of the physics of hadrons. Next, we study the phase transition which links the models thanks to the $\Gamma$-convergence.The last part is devoted to the study of another model from the physics of hadrons in which the wave functions are perfectly confined. We give some preliminary results.