Аннотация
(abridged) Elliptical cluster galaxies are successively stripped of their
gaseous atmospheres due to their motion through the ICM. The stripped galactic
gas forms a 'tail' in the galaxy's wake. Deep X-ray observations reveal the
fine-structure of the gas tail and of the interface between galactic gas and
ICM. This fine-structure depends on dynamic conditions (galaxy potential,
initial gas contents, orbit in the host cluster), stripping stage (early
infall, pre-/post-pericenter passage), and on the still ill-constrained ICM
plasma properties (thermal conductivity, viscosity, magnetic field structure).
In a series of papers, we aim at disentangling dynamic and plasma effects in
order to use observed stripped ellipticals as probes of the ICM plasma
properties. This first paper determines flow phases and flow patterns of
successive gas stripping by means of hydrodynamical simulations. During
quasi-steady stripping, the flow of ICM around the remnant atmosphere is
similar to the flow around solid bodies, including a 'deadwater region'
downstream of the remnant atmosphere. The size and shape of the galaxy's
remnant atmosphere is shaped by the ambient flow. Gas removal takes place
predominantly at the sides of the remnant atmosphere. The downstream atmosphere
is shaped into a tail because it is shielded from the ICM wind and thus is not
stripped easily. This remnant tail contains only unstripped, unmixed galactic
gas. Paper II of this series describes the effect of viscosity on flow patterns
and resulting observable features. While the qualitative results are generic,
we aim at the most direct comparison to observations and tailored our
simulations to the Virgo elliptical galaxy M89 (NGC 4552). Paper III of this
series compares in detail new deep Chandra and archival XMM-Newton observations
to our simulations.
Описание
[1409.6300] Stripped elliptical galaxies as probes of ICM physics: I. Tails, wakes, and flow patterns in and around stripped ellipticals
Линки и ресурсы
тэги