Turbulence in the tail of a jellyfish galaxy

0571484 - ASÚ 2024 RIV US eng J - Článek v odborném periodiku
Li, Y. - Luo, R. - Fossati, M. - Sun, M. - Jáchym, Pavel
Turbulence in the tail of a jellyfish galaxy.
Monthly Notices of the Royal Astronomical Society. Roč. 521, č. 3 (2023), s. 4785-4791. ISSN 0035-8711. E-ISSN 1365-2966
Grant CEP: GA MŠMT LM2023059
Institucionální podpora: RVO:67985815
Klíčová slova: hydrodynamics * instabilities * plasmas
Obor OECD: Astronomy (including astrophysics,space science)
Impakt faktor: 4.8, rok: 2022
Způsob publikování: Omezený přístup
https://doi.org/10.1093/mnras/stad874

When galaxies move through the intracluster medium (ICM) inside galaxy clusters, the ram pressure of the ICM can strip the gas from galaxies. The stripped gas forms tails on the trailing side. These galaxies are hence dubbed 'jellyfish galaxies'. ESO 137-001 is a quintessential jellyfish galaxy located in the nearest rich cluster, the Norma cluster. Its spectacular multiphase tail has complex morphology and kinematics both from the imprinted galaxy's interstellar medium (ISM) and as a result of the interactions between the stripped gas and the surrounding hot plasma, mediated by radiative cooling and magnetic fields. We study the kinematics of the multiphase tail using high-resolution observations of the ionized and the molecular gas in the entire structure. We calculate the velocity structure functions in moving frames along the tail and find that turbulence driven by Kelvin-Helmholtz (KH) instability quickly overwhelms the original ISM turbulence and saturates at similar to 30 kpc. There is also a hint that the far end of the tail has possibly started to inherit pre-existing large-scale ICM turbulence likely caused by structure formation. Turbulence measured by the molecular gas is generally consistent with that measured by the ionized gas in the tail but has a slightly lower amplitude. Most of the measured turbulence is below the mean free path of the hot ICM (similar to 11 kpc). Using warm/cool gas as a tracer of the hot ICM, we find that the isotropic viscosity of the hot plasma must be suppressed below 0.01 per cent Spitzer level.
Trvalý link: https://hdl.handle.net/11104/0343101