Associated production of J/psi and Dstar in pp collisions at sqrt(s) = 13 TeV with the full Run 2 data in CMS detector and CMS-RPC upgrade project studies

FERREIRA FILHO, M. B. Associated Production of J/?? and D??? in pp Collisions at???s = 13 TeV With the Full Run 2 Data in CMS Detector and CMS-RPC UpgradeProject Studies. 2023. 287 f. Tese (Doutorado em F??sica) ??? Instituto de F??sica ArmandoDias Tavares, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2023.In this work, two main subjects are addressed. The first topic concerns the Compact Muon Solenoid-Resistive Plate Chamber (CMS-RPC) upgrade project, where twomain sub-topics are studied. In the first sub-topic, the performance of eco-friendly gasmixtures for the Resistive Plate Chambers (RPC) is analyzed. The performance of twogas mixtures (HFO (35%), CO2 (60%), i-C4 H10 (4%), SF6 (1%) and HFO (25%), CO2(69%),i-C4 H10 (5%), SF6 (1%)) based on CO2 -tetrafluoropropene is compared with theperformance of the standard gas mixture (C2 H2 F4 (95.2%), i-C4 H10 (4.5%), SF6 (0.3%))used in the RPCs of the Compact Muon Solenoid (CMS) experiment. The performanceof both ecogas mixtures is slightly lower than the performance of the standard gas mixture. Still, they can be classified as good candidates and more tests must be performedto validate the long-term operation. In the second sub-topic, the study of the aging ofan iRPC prototype is discussed. The data-taking is performed at the Gamma Irradiation Facility (GIF++), a place that combines a 14 TBq 137 Cs source with a high-energyparticle beam. The performance results during the beam tests are satisfactory. However,during the long-term operation, the currents in one of the gaps started to increase afterthe accumulation of 50 mC/cm2 of charge. The cause is still being ???studied. In the second???topic, the associated production of J/?? and D in pp collisions at s = 13 TeV with thefull Run 2 in CMS detector is analyzed. This is the first time that this measurement was???performed. The cross-section has been measured in the fiducial region, 4 < pD< 60TJ/??D???J/??GeV/c, |y | < 2.1, 25 < pT < 100 GeV/c, |y | < 1.2 as 585 ?? 6 (stat) ?? 52 (sys)pb, where the fraction due to the DPS contribution was estimated to be 97.5%. In this+0.25scenario, the effective cross-section was found to be 2.53+0.09???0.08 (stat) ???0.29 (sys) mb.Keywords: Double Parton Scattering. Effective Sigma. Ecogas. Resistive Plate Chamber.American Chemical Society, which can be understood as a registry number. Therefrigerant identifier is the commercial name of the gas. The main informationconcerning the impact of the gas on the environment is given by the GWP andODP.Source: [135]. Adapted by the author.