Heavy quarkonium production is not fully understood, but often described by two different models, the Color Singlet Model (CSM), and the Color Octet Model (COM). Previous measurements at the Tevatron collider by the CDF and D0 experiments are not fully in agreement with predicted observables from either model. The Relativistic Heavy Ion Collider (RHIC), and the Solenoidal Tracker At RHIC (STAR) is well suited to further explore heavy quarkonium production. The Heavy Flavor program in STAR encompasses various heavy-flavor analyses, taking advantage of its large solid-angle acceptance, including measurements that explore the properties of heavy quarkonium production using J/ψ and Upsilon (Υ) reconstructions via the di-electron channel, in p+p, d+Au, Cu+Cu, and Au+Au collision systems. This thesis presents results of reconstructed Upsilon (Υ) to study the Upsilon(nS) [n = 1, 2, 3] line- shape and measurements of the production-related observables of spin-alignment (‘polarization’) and Upsilon + hadron correlations (Υ + h) to investigate the Upsilon production mechanism, using triggered data from Run-8 (2008) d+Au and Run-9 (2009) p+p collisions at sqrt(sN N) = 200 GeV, detected at STAR. The result of the spin-alignment measurement is α = 1 ± 0.3 with χ^2 /n.d.f. = 18.71/7 indicating a large (transverse) polarization. The measurement of hadronic activity near the vicinity of an Upsilon, within current uncertainties, is in reasonable agreement with both CSM and COM predictions from PYTHIA, but slightly favors the COM prediction for the near-side Υ + h correlation.

Résumé indisponible / Résumé indisponible

A measured cross section of simultaneously produced Υ(1S) and J/ψ mesons is performed using 20 fb-1 integrated luminosity in proton-proton collisions at √s=8 TeV center of mass energy recorded by the CMS detector. Both mesons are fully reconstructed from their final states, μ+ μ-. To extract the signal yield, an extended maximum likelihood fit is used on two (invariant mass of Υ(1S) and J/ψ) and three (invariant mass of Υ(1S) and J/ψ, cτ) dimensional components. A two-dimensional extended likelihood fit is used for the signal yield of data and a three-dimensional extended likelihood fit is used to know the possibility of displaced J/ψ candidate events arising from a B meson decay. A data embedding method is used to correct the efficiency in the data. The cross section in the fiducial region, defined as |y|<2.0, is determined to be 16.5±3.6(stat)±2.6(syst) pb. In order to improve the physics measurements capabilities for the harsh radiation environments at Large Hadron Collider (LHC), radiation hard detectors are needed. Secondary Emission Method (SEM) is a technique to measure the energy of particles such as e, n, and p in extreme radiation environments. Secondary Emission Ionization Calorimetry is a new technique for high radiation conditions. We designed two different types of test boards to test Hamamatsu single anode R7761 and multi-anode R5900-00-M16 PMTs and compared average gain values for both SE and PMT modes. We found that both values (SE and PMT) were comparable, which means the test boards that were developed perform very well and they could be used at Fermilab Test Beam Facility or in the CERN H2 beam area for the detection of minimum ionizing and showering particles.

This dissertation dicusses two topics; the cross section measurement of ϓ(1S) meson pair production [1] and simulation studies of High Granularity Calorimetry (HGCal). The first part of the dissertation is dedicated for the analysis of ϓ(1S) meson pair production and measurement of its cross section. The data for this analysis were collected by the CMS experiment at Large Hadron Collider (LHC) at a center-of-mass energy of 8 TeV and correspond to an integrated luminosity of 20.7 fb −1 . Simultaneous production of two ϓ(1S) mesons is observed for the first time with 38 events, corresponding to a local significance exceeding five standard deviations from the expected combinatorial background b-quark decays. Both ϓ(1S) candidates are fully reconstructed via their decays to μ + μ − . The fiducial acceptance of the detector is measured from the simulation and is defined by an absolute Υ(1S) rapidity smaller than 2.0. To minimize the model-dependence, the acceptance and efficiency corrections are calculated on an event-by-event basis using measured ϓ meson and muon momenta. The fiducial cross section of ϓ(1S) meson production, assuming both ϓ(1S) mesons decay isotropically, is measured to be 68.8 ± 12.7 (stat) ± 7.4 (syst) ± 2.8 (B) pb, where the third uncertainty comes from the uncertainty in the branching fraction of ϓ(1S) decays to μ + μ − . Different assumptions about ϓ productions imply modifications to the cross section ranging from −38% to +36%. Cross section measurement of ϓ pair production will provide better understanding of the parton vstructure of proton and enhance precision of existing particle production models. LHC is planning to increase luminosity and energy of colliding protons. Due to accumulated radiation damage and to improve detector performance CMS experiment is expected to undergo upgrade plans. Hadron calorimeter is among them, and it is planned to be replaced with better performance high granularity calorimetry (HGCal). HGCal needs to be integrated with existing components of CMS and its smooth functioning is essential. The second part of the dissertation describes simulation studies performed to validate readiness of HGCal for the Phase II upgrade.

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ALICE est dédié à l'étude d'un état de la matière nucléaire dans lequel les quarks et les gluons ne sont plus confinés dans les hadrons, qui est appelé Quark Gluon Plasma (QGP). La production de bottomonia (états liés beauté antibeauté) est sensible au QGP parce-que les états du bottomonium sont formés avant la formation du QGP et traversent le plasma pendant son évolution. L'objectif principal de cette thèse est la mesure des modification des mésons Upsilon dans le canal de désintégration en deux muons en collisions Pb-Pb à √SNN = 5.02 TeV. En outre, un nouveau framework pour l'analyse des performances des détecteurs utilisés pour l'identification des muons a été réalisé et utilisé pour l'analyse des données du RUN1 et RUN2 du LHC. Enfin, et avec l’objectif d’optimiser des résultats de l’analyse, un nouvel algorithme d’identification de muons a été développé. Cet algorithme deviendra nécessaire pour faire face aux nouvelles conditions de prise de données du RUN3, pendant lequel une reconstitution quasi-en ligne du détecteur est prévue. / ALICE is devoted to the study of a deconfined state of nuclear matter called Quark Gluon Plasma (QGP), in which quarks and gluons behave as free particles. The bottomonium (bound states of beauty-anti beauty quark) production is affected by the presence of the QGP, since bottomonium states are produced sooner than the QGP and witness the whole evolution of the plasma. In this analysis the data coming from Pb-Pb collisions have been analysed in order to detect possible modifications of the production rates in the dimuon decay channel, with respect to the rates observed in proton-proton collisions. Furthermore, the performances of the detectors involved in the muon identification during the LHC RUN1 and RUN2 has been tested using a new analysis framework implemented as part of this thesis. Finally, in order to optimize the results of future analyses, a new muon identification algorithm has been developed and tested. This algorithm will become necessary in the LHC RUN3 running conditions, when the much higher luminosity will require a quasi online reconstruction of data.

BABAR is a particle physics experiment at the Stanford Linear Accelerator Center (SLAC). The purpose of BABAR is to study matter-antimatter asymmetry in the bottom quark system. At SLAC, electons and positrons collide, which annihilate and decay into a variety of daughters. An Upsilon(4S) meson is one of the possible daughters. An Upsilon(4S) decays into a B meson and an anti-B meson more than 96% of the time. A B meson has an anti-bottom quark and an anti-B meson has a bottom quark. The purpose of this thesis is to measure how many Upsilon(1S) originated from Upsilon(4S) in the entire BABAR data set. This thesis compares on-peak data and off-peak data. On-peak data was taken at center of mass energy 10.58GeV. One of the possible interactions is e+e− -> Upsilon(4S) since the mass of Upsilon(4S) is 10.58GeV/c^2. On-peak data, taken at center of mass energy 10.54GeV, is not enough to have any BB pairs because 10.54GeV is less than the mass of an Upsilon(4S). This thesis can be useful for BABAR physicist because it helps set an upper limit on how many BB pairs there are in the entire BABAR data set. In other words, it sets an upper limit on how much more than 96% does Upsilon(4S) decay to BB. Measurement of the decay of Upsilon(4S) -> Upsilon(1S) + X give evidence for non-BB decays of the Upsilon(4S). The final results of this study show that there were (110 +- 3) × 10^5 Upsilon(1S) on-peak, of which (10 +- 9) × 10^5 originated from an Upsilon(4S). Increasing the centre of mass energy from 10.54GeV to 10.58GeV increases the Upsilon(1S) production by (10 +- 8)%.

O plasma de quarks e glúons é uma previsão da cromodinâmica quântica e experimentos em aceleradores de alta energia têm encontrado evidências experimentais de sua criação em colisões de íons pesados relativísticos. Uma dessas evidências foi proposta por Matsui e Satz [1] que prevê a supressão de estados de heavy quarkonium na existência deste plasma. Este projeto tem como objetivo obter a seção de choque da produção de no experimento STAR em colisões p+p e d+Au com energia no centro de massa de 200GeV e calcular o fator de modificação nuclear Rab. Para tal, foi necessário reconstruir os através de seu decaimento leptônico. Os subdetectores do STAR utilizados foram o TPC e BEMC. Os valores encontrados para seção de choque foram de 3i=1 (nS)e-e+(nS)p+p= 84 ±9(stat)+18-19(sist)pb e 3i=1 (nS)e-e+(nS)d + Au = 41 ± 4(stat) +7-8(sist)nb para as produções pp2009 e dAu2008, respectivamente. Os valores se encontram compatíveis com os teóricos calculados pelo modelo de evaporação de cor. O Rab experimental vale 1.24 ± 0.18(stat)+0.35 0.38(sist). / The quark and gluon plasma is a prediction of QCD, and high energy experiments have studied evidences of its creation in relativistic heavy ion collisions. One of these evidences was proposed by Matsui and Satz [1] that provides a experimental signature of the creation of the plasma, observing an anomalous supression on the heavy quarkonium production. This project aims to get production cross section in the STAR experiment in collisions p+p and d+Au with energy in the center of mass of 200GeV and calculate the nuclear modification factor Rab. To this end, it was necessary to reconstruct the from his leptonic decay. The subsystems used in this analysis were the TPC, BEMC and the heavy quarkonia trigger system. The values for the cross sections were 3i=1 (nS)e-e+(nS)p+p= 84 ±9(stat)+18-19(sist)pb and 3i=1 (nS)e-e+(nS)d + Au = 41 ± 4(stat) +7-8(sist)nb for pp2009 and dAu2008 productions, respectively. These values are compatible with the theoretical calculated by the color evaporation model. The determined value for the factor Rab was 1.24 ± 0.18(stat)+0.35 0.38(sist).

O plasma de quarks e glúons é uma previsão da cromodinâmica quântica e experimentos em aceleradores de alta energia têm encontrado evidências experimentais de sua criação em colisões de íons pesados relativísticos. Uma dessas evidências foi proposta por Matsui e Satz [1] que prevê a supressão de estados de heavy quarkonium na existência deste plasma. Este projeto tem como objetivo obter a seção de choque da produção de no experimento STAR em colisões p+p e d+Au com energia no centro de massa de 200GeV e calcular o fator de modificação nuclear Rab. Para tal, foi necessário reconstruir os através de seu decaimento leptônico. Os subdetectores do STAR utilizados foram o TPC e BEMC. Os valores encontrados para seção de choque foram de 3i=1 (nS)e-e+(nS)p+p= 84 ±9(stat)+18-19(sist)pb e 3i=1 (nS)e-e+(nS)d + Au = 41 ± 4(stat) +7-8(sist)nb para as produções pp2009 e dAu2008, respectivamente. Os valores se encontram compatíveis com os teóricos calculados pelo modelo de evaporação de cor. O Rab experimental vale 1.24 ± 0.18(stat)+0.35 0.38(sist). / The quark and gluon plasma is a prediction of QCD, and high energy experiments have studied evidences of its creation in relativistic heavy ion collisions. One of these evidences was proposed by Matsui and Satz [1] that provides a experimental signature of the creation of the plasma, observing an anomalous supression on the heavy quarkonium production. This project aims to get production cross section in the STAR experiment in collisions p+p and d+Au with energy in the center of mass of 200GeV and calculate the nuclear modification factor Rab. To this end, it was necessary to reconstruct the from his leptonic decay. The subsystems used in this analysis were the TPC, BEMC and the heavy quarkonia trigger system. The values for the cross sections were 3i=1 (nS)e-e+(nS)p+p= 84 ±9(stat)+18-19(sist)pb and 3i=1 (nS)e-e+(nS)d + Au = 41 ± 4(stat) +7-8(sist)nb for pp2009 and dAu2008 productions, respectively. These values are compatible with the theoretical calculated by the color evaporation model. The determined value for the factor Rab was 1.24 ± 0.18(stat)+0.35 0.38(sist).

Thesis advisor: Julia E. Grigsby / "Ozsváth, Stipsicz and Szabó define a one-parameter family {ϒᴋ(t)}t∈[₀,₂] of Heegaard Floer knot invariants for knots K ⊂ S³ . We generalize ϒᴋ (t) to knots in any" "rational homology sphere. We study the ϒ−invariant of a fibered knot. We prove that the ϒ−invariant can never reach its minimum slope if the monodromy of the fibration is not right-veering. / Thesis (PhD) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Mathematics.