Banca de QUALIFICAÇÃO: WELLINGTON LUIZ RIBEIRO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : WELLINGTON LUIZ RIBEIRO
DATA : 09/12/2021
HORA: 14:00
LOCAL: remoto
TÍTULO:

Propagation of Neutrinos as Open Quantum Systems: Investigating neutrino decoherence using extra-galactic sources

PÁGINAS: 50
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Física
SUBÁREA: Física das Partículas Elementares e Campos
ESPECIALIDADE: Teorias Específicas e Modelos de Interação; Sistemática de Partículas; Raios Cósmicos
RESUMO:

The first ideas treating neutrinos as open quantum systems date back to the late 1990s and early 2000s.
Although about 20 years have passed, only in the recent years this subject has drawn more attention. It happened probably because of the realization that neutrino decoherence may be a probe in the search of new physics. The incoherent dynamics is phenomenologically described using the Lindblad master equation in most of the cases. The decoherece parameters are taken ad hoc to depend on powers of the neutrino energy. The most common scenarios where these ideas are applied are atmospheric and accelerator neutrinos. Although these works provide important restrictions on decoherence parameters, we argue that there is a lack of description of the fundamental physics. It limits the discovery of the origin of the decoherence as well as their explicit expressions.

In this work, different master equations are derived to describe the propagation of neutrinos coming from extragalactic sources. I show that neutrino-dark matter interaction may cause an irreversible neutrino disappearance. Moreover, based on the scale of distances involved, I compute tight limits for neutrino-ultralight dark matter coupling constant. I show that, for this dark matter model, neutrinos can disappear irreversibly even for interactions 29 orders of magnitude smaller than the standard electroweak coupling.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1545176 - MARCELO AUGUSTO LEIGUI DE OLIVEIRA
Membro Titular - Examinador(a) Interno ao Programa - 1676798 - CELSO CHIKAHIRO NISHI
Membro Titular - Examinador(a) Externo ao Programa - 1762413 - LUCIANO SOARES DA CRUZ
Membro Suplente - Examinador(a) Interno ao Programa - 3065679 - BRENO MARQUES GONCALVES TEIXEIRA
Membro Suplente - Examinador(a) Interno ao Programa - 1544374 - ALEX GOMES DIAS