Merging Driven Evolution of High Redshift Galaxies in a Universe with OMEGA/0=1

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

124

Scientific paper

This paper introduces a unifying model of galaxy formation which can answer two questions suggested by recent data on high-redshift galaxies. These concern the ages of, and star-formation history in distant radiogalaxies, and the nature of the large number of field galaxies, revealed by faint galaxy counts. First, we show that the arguments favouring small ages (a few 10^8^ yr) as a unique solution for high-redshift radiogalaxies are weak, and inconsistent with the IR Hubble diagram. Then, in a universe with the density parameter {OMEGA}_0_ = 1 favoured by the inflationary scenario, we introduce a new scheme based on number evolution in addition to pure luminosity evolution: present-day galaxies result from the merging of a large number of building blocks. Models of basic luminosity and colour evolution fit the current Hubble sequence and the comoving number of these blocks evolves as (1+z)eta^. Field galaxies observed in faint counts are fitted with an evolutionary factor η~1.5 in the observable redshift range (z<=4), while the most distant radiogalaxies would be objects accreting the available building blocks more rapidly than this average rate. Star formation can begin early in the blocks (at z>=5), while radio jets would only be responsible for current star formation. This would explain the alignment of optical images with the radio axes, and the more compact IR images. The dispersion of the IR Hubble diagram is consistent with such a model.

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

Merging Driven Evolution of High Redshift Galaxies in a Universe with OMEGA/0=1 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 Merging Driven Evolution of High Redshift Galaxies in a Universe with OMEGA/0=1, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Merging Driven Evolution of High Redshift Galaxies in a Universe with OMEGA/0=1 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-841637

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