The global warming of group satellite galaxies
Recent studies adopting λ Re , a proxy for specific angular momentum, have highlighted how early-type galaxies (ETGs) are composed of two kinematical classes for which distinct formation mechanisms can be inferred. With upcoming surveys expected to obtain λ Re from a broad range of environments (e.g...
Published in: | Monthly Notices of the Royal Astronomical Society |
---|---|
Main Authors: | , |
Format: | Text |
Language: | English |
Published: |
Oxford University Press
2016
|
Subjects: | |
Online Access: | http://mnras.oxfordjournals.org/cgi/content/short/460/4/3968 https://doi.org/10.1093/mnras/stw960 |
Summary: | Recent studies adopting λ Re , a proxy for specific angular momentum, have highlighted how early-type galaxies (ETGs) are composed of two kinematical classes for which distinct formation mechanisms can be inferred. With upcoming surveys expected to obtain λ Re from a broad range of environments (e.g. SAMI, MaNGA), we investigate in this numerical study how the λ Re –ϵ e distribution of fast-rotating dwarf satellite galaxies reflects their evolutionary state. By combining N -body/SPH simulations of progenitor disc galaxies (stellar mass ≃109 M ⊙ ), 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 Re –ϵ e distribution at z < 0.1 reproduces its observational counterpart from the ATLAS3D/SAURON projects. We predict therefore how the observed λ Re –ϵ e distribution of a group evolves according to these ensemble tidal interactions. |
---|