Study of the medium effects in jet observables in relativistic heavy-ion collisions

• Ano de defesa: 2023
• Autor(a) principal: Paulino, Maria Monalisa de Melo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Cromodinâmica Quântica.; Física de Altas Energias; Heavy-Ion; Hidrodinâmica; High Energy Physics; Hydrodynamics.; Íons Pesados; Plasma de Quarks e Glúons
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/43/43134/tde-22032024-172237/

This work aims to study phenomenologically the influence of the medium formed in collisions between heavy ions on the propagation of jets originating from the fragmentation of partons. The project implements a model of partonic propagation a non-homogeneous and hydrodynamically expanding medium using the Monte Carlo event generators JEWEL (Jet Evolution With Energy Loss), m T$_R$ENTo for initial medium conditions, and the (2+1)D v-USPhydro for the event-by-event evolution of a realistic medium. The group has previously combined these models, enabling the study of a new series of observables related to jets generated by heavy quarks beyond $R_$, such as di-jet ($x_J$), jet mass ($M_$) and semi-inclusive hadron-jet. These observables have been the subject of numerous experimental measurements, but there is a scarcity of models that seek to describe their behavior. All observables are presented for central and peripheral PbPb collisions at $2.76$~TeV and $5.02$~TeV, following the experimental setups of the LHC Run-2, for anti-k$_T$ jets with varying radius R from $0.2$ to $1.0$. The simulated nuclear modification factor $R_$ and jet mass $M_$ satisfactorily reproduce experimental results for both central and peripheral collisions when using the combination of models without thermal background subtraction. On the other hand, the semi-inclusive hadron-jet (h-jet) and the di-jet $x_J$ observables have demonstrated their indifference to changes in the surrounding medium. The results with respect to centrality and the value of R suggest the opportunity to gain a deeper understanding of the medium response using JEWEL with thermal subtraction.