Banca de QUALIFICAÇÃO: DIEGO SILVA VIEIRA GONCALVES
Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.DISCENTE : DIEGO SILVA VIEIRA GONCALVES
DATA : 15/10/2021
HORA: 14:00
LOCAL: Por participação remota.
TÍTULO:
Axion phenomenology in Two-Higgs Doublet Model with extra gauge symmetry $U(1)_X$
PÁGINAS: 50
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Física
SUBÁREA: Física das Partículas Elementares e Campos
RESUMO:
In this work, we propose a Two-Higgs Doublet Model (2HDM) extension of the Standard Model (SM). The flavor-changing neutral currents (FCNC) are forbidden by an extra gauge symmetry, $U(1)_X$. This model offers simultaneous solutions to the problems of strong CP and dark matter with the addition of an anomalous global symmetry, $U(1)_{PQ}$, and of the neutrino masses with a Dirac seesaw mechanism realization. The neutrinos masses are suppressed by the ratio of the breaking scales of the two extra symmetries of the model, leading to the characterization of the breaking scale of $U(1)_X$ as intermediate. Signals may be within experimental reach in the next generations of colliders. The gauge boson associated with $U(1)_X$ does not mix the SM $Z$ boson. There are hints this is a general feature in extended scalar sector models. This model's axion may explain the observed abundance of dark matter if $U(1)_{PQ}$ breaking scale is high enough. Preferred regions in the axion parameter space are identified. Lastly, we notice that the constraint on the axion decay constant, $f_a$, by the flavor violating process $K^+ \to \pi^+ a$ is suppressed by the $U(1)_X$ breaking scale.
MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1676798 - CELSO CHIKAHIRO NISHI
Membro Titular - Examinador(a) Interno ao Programa - 3057567 - CHEE SHENG FONG
Membro Titular - Examinador(a) Interno ao Programa - 1676343 - PEDRO GALLI MERCADANTE
Membro Suplente - Examinador(a) Interno ao Programa - 1544422 - EDUARDO DE MORAES GREGORES
Membro Suplente - Examinador(a) Externo ao Programa - 1546626 - JOSE KENICHI MIZUKOSHI