Dynamics of Barred Galaxies in Triaxial Dark Matter Haloes

• Ano de defesa: 2010
• Autor(a) principal: Machado, Rubens Eduardo Garcia
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: astrophysics; dinâmica galáctica; galactic dynamics; galáxias: evolução; galáxias: halos; galaxies: evolution; galaxies: haloes; methods: numerical simulations; métodos: simulações numéricas; palavras-chave: astrofísica
• Link de acesso: http://www.teses.usp.br/teses/disponiveis/14/14131/tde-02122011-111155/

Cosmological N-body simulations indicate that the dark matter haloes of galaxies should be generally triaxial. Yet, the presence of a baryonic disc is believed to modify the shape of the haloes. The goal of this thesis is to study how bar formation is affected by halo triaxiality and how, in turn, the presence of the bar influences the shape of the halo. We performed a series of collisionless and hydrodynamical numerical simulations, using elliptical discs as initial conditions. Triaxial halos tend to become more spherical and we show that part of the circularisation of the halo is due to disc growth, but part must be attributed to the formation of a bar. We find that the presence of gas in the disc is a more efficient factor than halo triaxiality in inhibiting the formation of a strong bar.