Neutrino-nucleon scattering is an effective way to investigate the inner structure of the nucleon, to extract the Standard Model parameters and to explore heavy quarks production dynamics. In the last decades, several experiments have been constructed to study weak interactions of neutrinos with nucleons. One of them was CERN-WA95 experiment operated by the CHORUS collaboration. It is based on a hybrid detector with nuclear emulsion as a target followed by electronic devices. Nuclear emulsion provides three dimensional spatial information with an outstanding resolution of the order of one micron. Therefore, it is ideal to detect short-lived particles. A special technique has been developed to reconstruct events in the emulsion which allows to perform a detailed investigation of events such as charmed hadrons production by neutrinos. As a result, the backround in the selected charm sample is up to six times lower compared to similar experiments. Such a method also permits to make direct measurements of some quantities instead of model fittings. This thesis is devoted to the study of the muonic decays of charmed hadrons and their production in emulsion. Manual inspection of charm events gives a complete reconstruction of charm decay topology. The extraction of the inclusive muonic branching ratio is based on the ratios per number of charged daughters in charm decay. Such an approach allows to separetely measure the muonic branching ratios for neutral and charged charm particles. Finally, normalization of the events with a muon in the final state to the charged current events gives dimuon production rate which is found compatible with the previous experiments. On top of that, preliminary results are shown for Bjorken x distribution and for a direct measurement of the Vcd Cabbibo-Kabayashi-Maskawa matrix element.

Neutrino-nucleon scattering is an effective way to investigate the inner structure of the nucleon, to extract the Standard Model parameters and to explore heavy quarks production dynamics. In the last decades, several experiments have been constructed to study weak interactions of neutrinos with nucleons. One of them was CERN-WA95 experiment operated by the CHORUS collaboration. It is based on a hybrid detector with nuclear emulsion as a target followed by electronic devices. Nuclear emulsion provides three dimensional spatial information with an outstanding resolution of the order of one micron. Therefore, it is ideal to detect short-lived particles. A special technique has been developed to reconstruct events in the emulsion which allows to perform a detailed investigation of events such as charmed hadrons production by neutrinos. As a result, the backround in the selected charm sample is up to six times lower compared to similar experiments. Such a method also permits to make direct measurements of some quantities instead of model fittings. This thesis is devoted to the study of the muonic decays of charmed hadrons and their production in emulsion. Manual inspection of charm events gives a complete reconstruction of charm decay topology. The extraction of the inclusive muonic branching ratio is based on the ratios per number of charged daughters in charm decay. Such an approach allows to separetely measure the muonic branching ratios for neutral and charged charm particles. Finally, normalization of the events with a muon in the final state to the charged current events gives dimuon production rate which is found compatible with the previous experiments. On top of that, preliminary results are shown for Bjorken x distribution and for a direct measurement of the Vcd Cabbibo-Kabayashi-Maskawa matrix element.

A two-scintillator paddle muon telescope with variable angular acceptance at the earth's surface was used to study correlations between flux distribution and barometric pressure. The detector was placed in 2 different locations around Georgia State University with varying paddle separations of 0, 7, and 14 inches. Correlation and anti-correlation analyses were conducted by using the muon count from the detector along with the barometric pressure, surface temperature, stratospheric temperature and solar activity. It was observed that there was a short and long-term variation relationship between cosmic ray counts and barometric pressure and also cosmic ray counts and temperature. No significant relationship was found between cosmic ray flux and solar activity. A new two-scintillator paddle telescope with larger detecting area was constructed in order to observe a stronger correlation between cosmic ray flux and pressure.

abstract: The muon problem of flavor physics presents a rich opportunity to study beyond standard model physics. The as yet undiscovered bound state (μ+μ-), called true muonium, presents a unique opportunity to investigate the muon problem. The near-future experimental searches for true muonium will produce it relativistically, preventing the easy application of non-relativistic quantum mechanics. In this thesis, quantum field theory methods based on light-front quantization are used to solve an effective Hamiltonian for true muonium in the Fock space of |μ+μ-> , |μ+μ-γ> , |e+e->, |e+e-γ>, |τ+τ-> , and |τ+τ-γ> . To facilitate these calculations a new parallel code, True Muonium Solver With Front-Form Techniques (TMSWIFT), has been developed. Using this code, numerical results for the wave functions, energy levels, and decay constants of true muonium have been obtained for a range of coupling constants α. Work is also presented for deriving the effective interaction arising from the |γγ sector’s inclusion into the model. / Dissertation/Thesis / Doctoral Dissertation Physics 2016

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-11T11:12:28Z No. of bitstreams: 1 viniciusbarbosaschettino.pdf: 29158699 bytes, checksum: 73147768684934f5b11f6c844b4bbc4d (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-26T11:57:35Z (GMT) No. of bitstreams: 1 viniciusbarbosaschettino.pdf: 29158699 bytes, checksum: 73147768684934f5b11f6c844b4bbc4d (MD5) / Made available in DSpace on 2016-02-26T11:57:35Z (GMT). No. of bitstreams: 1 viniciusbarbosaschettino.pdf: 29158699 bytes, checksum: 73147768684934f5b11f6c844b4bbc4d (MD5) Previous issue date: 2014-02-14 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / O LHC é o mais energético acelerador de partículas já construído. Operado pelo CERN, essa fantástica máquina encontra-se no subterrâneo, na região da fronteira franco-suíça. Um de seus principais experimentos, o ATLAS, está atualmente passando por um período de parada técnica planejada, visando concomitantemente a consolidação da estrutura eletrônica do detector e a substituição de tecnologias, preparando o experimento para um novo estágio de operação do LHC, em que haverá um grande aumento na taxa de colisões entre prótons. Nesse contexto, essa dissertação abordará o estudo e o desenvolvimento de sistemas eletrônicos para o TileCal, um dos calorímetros do ATLAS. Principalmente, serão discutidos dois novos sistemas: O Sistema Móvel de Checagem da Integridade das Gavetas, conhecido como Mobi- DICK, e o projeto Tile-Muon. Relativamente ao primeiro, serão expostos detalhes da quarta versão de um sistema utilizado para realizar checagens quantitativas e qualitativas da eletrônica do TileCal. Esta nova versão, implementa ainda a estrutura que possibilita a realização de testes nas novas tecnologias que serão utilizadas no calorímetro. O ambicioso projeto Tile-Muon visa a utilização do TileCal para identificação de múons, com o objetivo de tornar mais eficiente a seleção de eventos do ATLAS. Essa proposta requer o desenvolvimento de uma nova estrutura eletrônica de suporte, que será apresentada nessa dissertação. Apresentaremos análises feitas com o MobiDICK sobre a eletrônica do TileCal, que mostrou boa performance, e também uma caracterização do sinal de múons, estudo fundamental para a validação e o desenvolvimento do projeto Tile-Muon. / The LHC is the most energetic particle accelerator ever built. Run by CERN, this fantastic machine lays underground, near the Franco-Swiss border. One of its main experiments, ATLAS, is currently going through a planned technical stop, targeting both a consolidation of the detector’s electronics and a technology replacement, preparing the experiment to a new stage in the LHC operation, where the protons collision rate will increase largely. In such context, this dissertation addresses the study and the development of electronic systems for TileCal, one of ATLAS calorimeters. Primarily, two new systems will be discussed: the Mobile Drawer Integrity Checking System, known as MobiDICK, and the Tile-Muon project. Regarding the former, we’ll bring details of the fourth version of a system used to check quantitatively and qualitatively the electronics of TileCal. This new version also provides the system with the ability to test the new technologies that will be used in the calorimeter. The ambitious Tile-Muon project aims at using TileCal for muon identification, with the goal of raising the efficiency of event selection in ATLAS. This proposal requires the development of a new electronic structure for support, which will also be presented in this dissertation. Analysis of TileCal’s electronics using MobiDICK will be shown, revealing good performance, along with a characterization of the muon signal, a fundamental study for validation and development of the Tile-Muon project.

Title: Tile Calorimeter response to muons Author: Tomas Javurek Department: Institute of Particle and Nuclear Physics Supervisor: RNDr. Tomas Davidek, Ph.D. Supervisors e-mail address: davidek@ipnp.troja.mff.cuni.cz Abstract: The aim of present work is investigation of Tile calorimeter (subde- tector of ATLAS experiment) response to muons. Muons can help to monitor spatial non-linearities in this hadronic detector. Graphs of unifromities are used for these purposes i.e. dependence of dE/dx (deposited energy per unit length) on azimuthal angle φ and polar angle θ which is represented by pseu- dorapidity η. Finally the dependence of dE/dx on energy was also studied. Keywords: TileCal, muon, uniformity, energy loss

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19747号 / 工博第4202号 / 新制||工||1648(附属図書館) / 32783 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 辻井 敬亘, 教授 吉崎 武尚, 教授 渡辺 宏 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

<p> LiHoxY1-xF4 is an insulating system where the Ho ions are magnetic. The crystal field gives an Ising character to the Ho ions, and the dominant interaction between them is through magnetic dipolar fields. For x=1, the system is a ferromagnet with a critical temperature of 1.54 K. The critical temperature decreases as x is decreased until x~0.25. At that point the long range order is destroyed, giving rise to a state with some characteristics of spin glass behavior.</p> <p> The study of this system is important because its Ising nature makes it a test ground for theoretical models. Interestingly, not only experiments and theory diverge in many points, but experimental data from different research groups are contradictory. In order to contribute to a clearer experimental picture, we performed μSR measurements in this system and we present our results in this thesis.</p> <p> In the ferromagnetic samples (x=1 and 0.45) we found that the internal field distribution at the muon site is quite broad, even in the x=1 system. Then it is possible that the magnetic field distribution at the Ho ions is broad as well. We show qualitatively how this broadening could explain a feature of the field-temperature phase diagram which is still not understood.</p> <p> For the more diluted samples (x=0.25, 0.12, 0.08, 0.045 and 0.018), we found that they all have the same qualitative behavior as a function of temperature and magnetic field. Our analysis of the data did not show any feature of canonical spin glass behavior. Instead, an analysis using dynamical Kubo-Toyabe functions show a temperature independent fluctuation rate of the Ho moments below ~0.5 K for all these samples. This behavior is characteristic of cooperative paramagnetic systems. We also found that the low temperature fluctuation rate decreases as x is decreased.</p> <p> To analyze the data from LiHoxY1-xF4 we developed microscopic models of μSR signals. These models are presented in this thesis and they correspond to stochastic models of signals using stretched magnetic field distributions; and the modeling of signals from systems with F-μ-F bond formation where the set of bonds does not have cubic symmetry.</p> / Thesis / Doctor of Philosophy (PhD)

This experiment attempts to measure the Michel parameter Rho in normal muon decay Mu to e nu_{e} nu_{mu} with a precision of 0.001. The Standard Model with pure V-A interaction gives 0.75 for this parameter. The world average value is 0.7518 +/- 0.0026. A deviation of the value of Rho from 0.75 will indicate new physics. The experiment, RHO, was carried out at the Los Alamos Meson Physics Facility (LAMPF) of Los Alamos National Laboratory (LANL) in New Mexico, USA, in 1993. The existing experimental set-up that was built for the MEGA experiment was used for the RHO measurement. The experiment was a collaboration of about 50 physicists from Los Alamos National Laboratory, Stanford University, Fermi National Accelerator Laboratory, Virginia Tech, Texas A University, Indiana University, Valparaiso University, University of Houston, University of Chicago and University of Virginia. The result of the experiment is in agreement with Standard Model. The precision of this measurement was dominated by systematic uncertainties due to the fact that the positron spectrometer used in the measurement was designed for another experiment. Thus, the data analysis here focused mainly on the determination of systematic errors. / Ph. D.

Thesis advisor: Michael J. Graf / Quantum spin liquids (QSL)’s have been one of the most hotly researched areas ofcondensed matter physics for the past decade. Yet, science has yet to unconditionally identify any one system as harboring a QSL state. This is because QSL’s are largely defined as systems whose electronic spins do not undergo a thermodynamic transition as T→0. Quantum spin liquids remain fully paramagnetic, including dynamical spin fluctuations, at T=0. As a result, distinguishing a QSL system from a conventionally disordered system remains an outstanding challenge. If a system spin freezes or magnetically orders, it cannot be a QSL. In this thesis I present published experiments I have performed on QSL candidate materials. By using muon spin rotation (μSR) and AC magnetic susceptibility I have evaluated the ground states of several candidates for the absence of long-range magnetic disorder and low-temperature spin-fluctuations. For the systems which order or spin-freeze, my research provided key knowledge to the field of frustrated magnetism. The systems I studied are as follows: The geometrically frustrated systems NaYbO2 and LiYbO2; the Kitaev honeycomb systems Cu2IrO3 and Ag3LiIr2O6; and the metallic kagome system KV3Sb5. Each of these systems brought new physics to the field of frustrated magnetism. NaYbO2 is a promising QSL candidate. LiYbO2 harbors an usual form of spiral incommensurate order that has a staggered transition. Cu2IrO3 has charge state disorder that results in a magnetically inhonogenious state. Ag3LiIr2O6 illustrates the role structural disorder plays in disguising long-range magnetic order. And finally, KV3Sb5 isn’t conventionally magnetic at all; our measurements ruled out ionic magnetism and uncovered a type-II superconductor. Our measurements on KV3Sb5 stimulated further research into KV3Sb5 and it’s unconventional electronic states. / Thesis (PhD) — Boston College, 2022. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.