gas question

[Andrzej Marecki]

> The origin of the gas is not completely clear. The standard idea is that
> the bulk of the gas (in fraction of mass) is primordial and collapsed with
> the dark matter when the system components (the groups that later merged
> into present-day clusters) collapsed.
> 
> However, the abundance of heavy elements is roughly 1/3 solar in
> clusters, instead of near-zero predicted if the gas wewre primordial.
> So, in the standard picture, the gas is polluted by galaxy winds caused by
> supernovae, and the bulk of the metals (heavy elements) comes from
> the galaxies, even though the galactic winds contribute little to the mass
> of the hot intracluster gas.

Gary, and how about the more "natural" explanation of that pollution with 
heavy elements. What I mean is that the intracluster gas (partly) comes
from... the galaxy collisions. Such collisions are inelastic w.r.t. the gas
and so the scenario seems to be the following:

1. The stars "pass through" although, of course, the structure/shape of the 
   galaxies is - as we perfectly know - significantly disturbed.
2. The galactic gas stays "in place"
3. The galactic gas heats up.

The net result is the following:

1. Galaxies emerging from collisions are deprived of some gas and since the 
gas mainly sits in galactic disks they are deprived of disks i.e. the become 
more and more elliptical. And *this* is what we actually observe!

2. Intracluster gas gets enriched by the galactic gas which in turn - as we 
perfectly know again - is reprocessed ("polluted") in the ("original") 
galaxies mainly by SNe.

3. The gas is hot because the kinetic energy of colliding galaxies is 
converted into the heat.

Sounds quite consistent and convincing, n'est ce pas? ;-)

Now, please criticise the above scenario, which - in fact - is not mine but
I have read it (it must have been a textbook) but don't remember where. :-)

Cheers, Andrzej