Publicação
Luminosity calibrations at the CERN compact muon solenoid experiment
| Resumo: | The quest to understand the fundamental nature of the universe drives the field of particle physics, centered around the Standard Model (SM), which describes the fundamental particles and three of the four known forces: electromagnetism, the weak force, and the strong force. Despite its success in explaining a wide range of phenomena, the SM does not address some of the most profound questions in physics, such as the nature of dark matter, the origin of mass hierarchies, and the unification of forces. Probing the SM with precision measurements is essential for uncovering potential new physics beyond the current theoretical framework. Particle colliders like the Large Hadron Collider (LHC) at CERN are at the forefront of this exploration, where measurements of cross sections are a crucial part of the physics program that tests the SM’s predictions. A cross section quantifies the likelihood of specific particle’s interactions, and accurate luminosity measurements are fundamental to determining these cross sections. Luminosity, L, is proportional to the rate of collisions, and thus any uncertainty in L translates into uncertainties in the cross sections, affecting the reliability of the conclusions drawn from experimental data. This thesis presents the preliminary calibration and measurement of luminosity for the 2023 protonproton collision data-taking period at a center-of-mass energy of 13.6 TeV with the CMS experiment. The absolute luminosity scale is established using the van der Meer (vdM) scan methodology, a technique that involves scanning the particle beams across each other to measure their overlap and calibrate the visible cross sections of the luminometers. A series of detectors were employed to provide real-time luminosity measurements, with systematic corrections and stability analyses ensuring consistent and accurate results The final integrated luminosity was measured as 32.74 fb-1 with a total uncertainty of 1.28%, representing the best preliminary luminosity results achieved by CMS. In addition to the experimental efforts, substantial software improvements were made to the codebases used in the analysis. These advancements enhanced data processing efficiency and streamlined the calibration workflow, enabling more rapid and reliable analysis iterations. |
|---|---|
| Autores principais: | Carneiro, Fábio Lucas Pereira |
| Assunto: | CERN CMS Luminosity Van der Meer Luminosidade |
| Ano: | 2024 |
| País: | Portugal |
| Tipo de documento: | dissertação de mestrado |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade do Minho |
| Idioma: | inglês |
| Origem: | RepositóriUM - Universidade do Minho |
| Resumo: | The quest to understand the fundamental nature of the universe drives the field of particle physics, centered around the Standard Model (SM), which describes the fundamental particles and three of the four known forces: electromagnetism, the weak force, and the strong force. Despite its success in explaining a wide range of phenomena, the SM does not address some of the most profound questions in physics, such as the nature of dark matter, the origin of mass hierarchies, and the unification of forces. Probing the SM with precision measurements is essential for uncovering potential new physics beyond the current theoretical framework. Particle colliders like the Large Hadron Collider (LHC) at CERN are at the forefront of this exploration, where measurements of cross sections are a crucial part of the physics program that tests the SM’s predictions. A cross section quantifies the likelihood of specific particle’s interactions, and accurate luminosity measurements are fundamental to determining these cross sections. Luminosity, L, is proportional to the rate of collisions, and thus any uncertainty in L translates into uncertainties in the cross sections, affecting the reliability of the conclusions drawn from experimental data. This thesis presents the preliminary calibration and measurement of luminosity for the 2023 protonproton collision data-taking period at a center-of-mass energy of 13.6 TeV with the CMS experiment. The absolute luminosity scale is established using the van der Meer (vdM) scan methodology, a technique that involves scanning the particle beams across each other to measure their overlap and calibrate the visible cross sections of the luminometers. A series of detectors were employed to provide real-time luminosity measurements, with systematic corrections and stability analyses ensuring consistent and accurate results The final integrated luminosity was measured as 32.74 fb-1 with a total uncertainty of 1.28%, representing the best preliminary luminosity results achieved by CMS. In addition to the experimental efforts, substantial software improvements were made to the codebases used in the analysis. These advancements enhanced data processing efficiency and streamlined the calibration workflow, enabling more rapid and reliable analysis iterations. |
|---|