Star Formation in Ram Pressure Stripped Tails

Monthly Notices of the Royal Astronomical Society (Impact Factor: 5.11). 03/2012; 422(2). DOI: 10.1111/j.1365-2966.2012.20737.x
Source: arXiv


We investigate the impact of star formation and feedback on ram pressure
stripping using high-resolution adaptive mesh simulations, building on a
previous series of papers that systematically investigated stripping using a
realistic model for the interstellar medium, but without star formation. We
find that star formation does not significantly affect the rate at which
stripping occurs, and only has a slight impact on the density and temperature
distribution of the stripped gas, indicating that our previous (gas-only)
results are unaffected. For our chosen (moderate) ram pressure strength,
stripping acts to truncate star formation in the disk over a few hundred
million years, and does not lead to a burst of star formation. Star formation
in the bulge is slightly enhanced, but the resulting change in the
bulge-to-disk ratio is insignificant. We find that stars do form in the tail,
primarily from gas that is ablated from the disk and the cools and condenses in
the turbulent wake. The star formation rate in the tail is low, and any
contribution to the intracluster light is likely to be very small. We argue
that star formation in the tail depends primarily on the pressure in the
intracluster medium, rather than the ram pressure strength. Finally, we compare
to observations of star formation in stripped tails, finding that many of the
discrepancies between our simulation and observed wakes can be accounted for by
different intracluster medium pressures.

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