Feedback from Galaxy Formation: Production and Photodissociation of Primordial Molecular Hydrogen

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Accepted for pubblication on ApJ vol 560, October 2001 with minor changes. 31 pages,including 12 figures and 1 table. Higher q

Scientific paper

10.1086/323051

We use one-dimensional radiative transfer simulations to study the evolution of H_2 gas-phase (H^- catalyzed) formation and photo-dissociation regions in the primordial universe. We find a new positive feedback mechanism capable of producing shells of H_2 in the intergalactic medium, which are optically thick in some Lyman-Werner bands. While these shells exist, this feedback effect is important in reducing the H_2 dissociating background flux and the size of photo-dissociation spheres around each luminous object. The maximum background opacity of the IGM in the H_2 Lyman-Werner bands is \tau_{H_2} ~ 1-2 for a relic molecular fraction x_{H_2}=2 x 10^{-6}, about 6 times greater than found by Haiman, Abel & Rees. Therefore, the relic molecular hydrogen can decrease the photo-dissociation rate by about an order of magnitude. The problem is relevant to the formation of small primordial galaxies with masses M_{DM} < 10^8 M_\odot, that rely on molecular hydrogen cooling to collapse. Alternatively, the universe may have remained dark for several hundred million years after the birth of the first stars, until galaxies with virial temperature T_{vir} > 10^4 K formed.

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

Feedback from Galaxy Formation: Production and Photodissociation of Primordial Molecular Hydrogen 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 Feedback from Galaxy Formation: Production and Photodissociation of Primordial Molecular Hydrogen, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Feedback from Galaxy Formation: Production and Photodissociation of Primordial Molecular Hydrogen will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-510333

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