Stellar migration in galaxy discs using the Chirikov diffusion rate
| Autor: | Herve Wozniak |
|---|---|
| Přispěvatelé: | Laboratoire Univers et Particules de Montpellier (LUPM), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) |
| Rok vydání: | 2019 |
| Předmět: |
Angular momentum
Diffusion FOS: Physical sciences Astrophysics Barred spiral galaxies 01 natural sciences Dynamical evolution [PHYS.PHYS.PHYS-COMP-PH]Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph] Extragalactic astronomy Galactic Archaeology Galaxy evolution 0103 physical sciences Galaxy formation and evolution N-body simulations 010306 general physics Adiabatic process 010303 astronomy & astrophysics ComputingMilieux_MISCELLANEOUS Galaxy stellar disks Astrophysics::Galaxy Astrophysics Physics Astronomy and Astrophysics Nonlinear Sciences - Chaotic Dynamics Astrophysics - Astrophysics of Galaxies Galaxy Barred spiral galaxy Distribution function Galaxy dynamics Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) [NLIN.NLIN-CD]Nonlinear Sciences [physics]/Chaotic Dynamics [nlin.CD] [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA] Astrophysics::Earth and Planetary Astrophysics Chaotic Dynamics (nlin.CD) Lindblad resonance |
| Zdroj: | The Astrophysical Journal The Astrophysical Journal, American Astronomical Society, 2020, 889 (2), pp.81. ⟨10.3847/1538-4357/ab5fd1⟩ |
| ISSN: | 0004-637X 1538-4357 |
| DOI: | 10.48550/arxiv.1912.03218 |
| Popis: | We are re-examining the problem of stellar migration in disc galaxies from a diffusion perspective. We use for the first time the formulation of the diffusion rates introduced by \citet{1979PhR....52..263C}, applied to both energy $E$ and angular momentum $L_\mathrm{z}$ in self-consistent N$-$body experiments. We limit our study to the evolution of stellar discs well after the formation of the bar, in a regime of adiabatic evolution. We show that distribution functions of Chirikov diffusion rates have similar shapes regardless the simulations, but different slopes for energy and angular momentum. Distribution functions of derived diffusion time scales $T_D$ have also the same form for all simulations, but are different for $T_D(E)$ and $T_D(L_\mathrm{z})$. Diffusion time scales are strongly dependent on $L_\mathrm{z}$. $T_D(E) \lesssim 1$~Gyr in a $L_\mathrm{z}$ range roughly delimited by the set of stellar bar resonances (between the Ultra Harmonic Resonance and the Outer Lindblad Resonance). Only particles with low $L_\mathrm{z}$ have $T_D(L_\mathrm{z}) \lesssim 10$ Gyr, i.e. the simulation length. In terms of mass fraction, 35 to 42% turn out to diffuse energy in a characteristic time scale shorter than 10 Gyr, i.e. simulations length, while 60 to 64% undergo the diffusion of the angular momentum on the same time scale. Both the diffusion of $L_\mathrm{z}$ and $E$ are important in order to grasp the full characterisation of the radial migration process, and we showed that depending on the spatial region considered, one or the other of the two diffusions dominates. Comment: 15 pages, 17 figures, Accepted for publication to ApJ |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|