The global warming of group satellite galaxies

• Main Authors: Yozin, C, Bekki, K
• Format: Text
• Language: unknown
• Published: arXiv 2016
• Subjects: Astrophysics of Galaxies astro-ph.GA; FOS Physical sciences; sami
• Online Access: https://dx.doi.org/10.48550/arxiv.1604.05807; https://arxiv.org/abs/1604.05807

Recent studies adopting $λ_{\rm Re}$, a proxy for specific angular momentum, have highlighted how early-type galaxies (ETGs) are composed of two kinematic classes for which distinct formation mechanisms can be inferred. With upcoming surveys expected to obtain $λ_{\rm Re}$ from a broad range of environments (e.g. SAMI, MaNGA), we investigate in this numerical study how the $λ_{\rm Re}$-$ε_{\rm e}$ distribution of fast-rotating dwarf satellite galaxies reflects their evolutionary state. By combining N-body/SPH simulations of progenitor disc galaxies (stellar mass $\simeq$10$^{\rm 9}$ M$_{\odot}$), their cosmologically-motivated sub-halo infall history and a characteristic group orbit/potential, we demonstrate the evolution of a satellite ETG population driven by tidal interactions (e.g. harassment). As a general result, these satellites remain intrinsically fast-rotating oblate stellar systems since their infall as early as $z=2$; mis-identifications as slow rotators often arise due to a bar/spiral lifecycle which plays an integral role in their evolution. Despite the idealistic nature of its construction, our mock $λ_{\rm Re}$-$ε_{\rm e}$ distribution at $z<0.1$ reproduces its observational counterpart from the ATLAS$^{\rm 3D}$/SAURON projects. We predict therefore how the observed $λ_{\rm Re}$-$ε_{\rm e}$ distribution of a group evolves according to these ensemble tidal interactions. : 8 pages, 2 tables, 6 figures, accepted for publication in MNRAS