Fragmentation of a Shock-Compressed Sheet of Primordial Gas

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

27

Galaxies: Formation, Instabilities, Shock Waves

Scientific paper

We estimate the fragment mass scale of a primordial gas sheet compressed by steady state shock waves with a wide variety of initial parameters. We estimate the perturbation growth timescale tau_MGR(~tau_ff) and consider that fragmentation occurs when tau_cool = tau_MGR, then calculate the Jeans mass at the fragmentation. It is shown that there are two fragment mass scales depending on the values of shock velocity and preshock density because of the trough of the cooling coefficient at T ~ 8000 K. As an application, we consider the disklike collapse of the protocloud just after the turnaround. We assume the standard cold dark matter model with h = 0.8 and Omega_bh^2 = 0.01 and estimate the typical shock velocity and preshock density for each mass scale at the collapse. Compared with our steady state shock results, there is found to be a critical mass ~10^8 M_&sun; which assorts the subsequent evolution of protoclouds. We suggest that this critical mass scale provides the observed minimum mass of the bright galaxy sequence and the mass scale of the first luminous objects.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Fragmentation of a Shock-Compressed Sheet of Primordial Gas does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Fragmentation of a Shock-Compressed Sheet of Primordial Gas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fragmentation of a Shock-Compressed Sheet of Primordial Gas will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-811569

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.