The imprint of the relative velocity between baryons and dark matter on the 21-cm signal from reionization

Details The imprint of the relative velocity between baryons and dark matter on the 21-cm signal from reionization The imprint of the relative velocity between baryons and dark matter on the 21-cm signal from reionization

2011-10-20

arxiv.org/abs/1110.4659v1

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

4 pages, 5 figures

Scientific paper

The post-recombination streaming of baryons through dark matter keeps baryons out of low mass (<10^6 solar masses) halos coherently on scales of a few comoving Mpc. It has been argued that this will have a large impact on the 21-cm signal before and after reionization, as it raises the minimum mass required to form ionizing sources. Using a semi-numerical code, we show that the impact of the baryon streaming effect on the 21-cm signal during reionization (redshifts z approximately 7-20) depends strongly on the cooling scenario assumed for star formation, and the corresponding virial temperature or mass at which stars form. For the canonical case of atomic hydrogen cooling at 10^4 Kelvin, the minimum mass for star formation is well above the mass of halos that are affected by the baryon streaming and there are no major changes to existing predictions. For the case of molecular hydrogen cooling, we find that reionization is delayed by a change in redshift of approximately 2 and that more relative power is found in large modes at a given ionization fraction. However, the delay in reionization is degenerate with astrophysical assumptions, such as the production rate of UV photons by stars.

Affiliated with

Also associated with

No associations

Rating

The imprint of the relative velocity between baryons and dark matter on the 21-cm signal from reionization 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 The imprint of the relative velocity between baryons and dark matter on the 21-cm signal from reionization, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The imprint of the relative velocity between baryons and dark matter on the 21-cm signal from reionization will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-84621