Chaos and dynamical trends in barred galaxies: bridging the gap between N-body simulations and time-dependent analytical models

Autor(es)

Manos, T. ^{[1, 2]} ; Machado, Rubens E. G. ^[3]

Afiliação do(s) autor(es)

^[1] Univ Maribor, CAMTP, SI-2000 Maribor - Slovenia

^[2] Univ Nova Gorica, Sch Appl Sci, SI-5270 Ajdovscina - Slovenia

^[3] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Monthly Notices of the Royal Astronomical Society; v. 438, n. 3, p. 2201-2217, MAR 2014.
• Citações Web of Science: 18

Resumo

Self-consistent N-body simulations are efficient tools to study galactic dynamics. However, using them to study individual trajectories (or ensembles) in detail can be challenging. Such orbital studies are important to shed light on global phase space properties, which are the underlying cause of observed structures. The potentials needed to describe self-consistent models are time dependent. Here, we aim to investigate dynamical properties (regular/chaotic motion) of a non-autonomous galactic system, whose time-dependent potential adequately mimics certain realistic trends arising from N-body barred galaxy simulations. We construct a fully time-dependent analytical potential, modelling the gravitational potentials of disc, bar and dark matter halo, whose time-dependent parameters are derived from a simulation. We study the dynamical stability of its reduced time-independent 2-degrees of freedom model, charting the different islands of stability associated with certain orbital morphologies and detecting the chaotic and regular regions. In the full 3-degrees of freedom time-dependent case, we show representative trajectories experiencing typical dynamical behaviours, i.e. interplay between regular and chaotic motion for different epochs. Finally, we study its underlying global dynamical transitions, estimating fractions of (un)stable motion of an ensemble of initial conditions taken from the simulation. For such an ensemble, the fraction of regular motion increases with time. (AU)

• Processo FAPESP: 09/54006-4 - Um cluster de computadores para o Departamento de Astronomia do IAG-USP e para o Núcleo de Astrofísica da UNICSUL
• Beneficiário: Elisabete Maria de Gouveia Dal Pino
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 13/11219-3 - Caos em galáxias: a conexão entre modelos analíticos dependentes do tempo e simulações de N-corpos
• Beneficiário: Rubens Eduardo Garcia Machado
• Modalidade de apoio: Auxílio à Pesquisa - Pesquisador Visitante - Internacional
• Processo FAPESP: 10/12277-9 - Simulações numéricas de colisões de aglomerados de galáxias
• Beneficiário: Rubens Eduardo Garcia Machado
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado