Vorticity rings in relativistic heavy ion collisions

Autor(es)

Vítor Hugo Ribeiro

• Tipo de documento: Dissertação de Mestrado
• Imprenta: Campinas, SP.
• Instituição: Universidade Estadual de Campinas (UNICAMP). Instituto de Física Gleb Wataghin
• Data de defesa: 2023-08-24

Membros da banca

Jun Takahashi; Pedro Cunha de Holanda; Cristiane Jahnke Fiorini da Silva

• Orientador: Jun Takahashi

Resumo

Relativistic heavy ion collisions represent a fascinating and intricate phenomena, where atomic nuclei collide at extremely high energies, creating an environment of extreme conditions that are impossible to measure directly. Despite this complexity, several results regarding such a scenario were obtained in the last decades and improved our knowledge about the fundamental properties of nuclear matter. Among these results, two of them - the collective behavior of the medium and the jet energy loss phenomenon - have served as strong signatures for the formation of a new state of nuclear matter known as Quark-Gluon Plasma (QGP). Recently, a new measurement regarding the vorticity-spin coupling was observed and set up new opportunities for exploring and extracting the characteristics of the QGP. Based on that picture, in this work, we employed a model that connects the fluid behavior and the jet energy loss to study the thermalization process of the energy-momentum currents deposited into the collision medium by a quenched jet. We performed a systematic study on the formation of vorticity rings inside the QGP and used the polarization of the particles as an observable to measure the ring effects. We expanded previous analysis on that model to a more realistic framework by considering non-central events and fluctuations in the initial conditions. The results of this work were obtained through the application of a state of art hybrid chain computer simulation [TRENTo + (3+1D)MUSIC + iSS]. With this simulation chain we reproduced the formation and evolution of the ring structure in a relativistic viscous hydrodynamic model and studied the sensitivity of a proposed ''ring observable'' ($\mathcal{R}^{t}_{\Lambda}$), which is experimentally measurable through the polarization of $\Lambda$ hyperons. We showed that this observable presents a robust aspect regarding fluctuating initial conditions and we also analyzed its dependence on different model parameters, such as jet's velocity, position, fluid's shear viscosity, and collision centrality. Our results show that the measurement of particle polarization can be a powerful tool to probe different properties of jet-medium interactions and also can offer a clear signal of the thermalization of the energy lost by a quenched jet (AU)

• Processo FAPESP: 21/10750-3 - Vorticidade no Quark-Gluon Plasma induzido por jatos em colisões de íons pesados relativísticos
• Beneficiário: Vítor Hugo Ribeiro
• Modalidade de apoio: Bolsas no Brasil - Mestrado