New Improved Photometric Redshifts of Galaxies in the HDF

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

24 pages including 16 eps figures; accepted for publication in ApJ

Scientific paper

10.1086/308794

We report new improved photometric redshifts of 1048 galaxies in the Hubble Deep Field (HDF). A standard chi^2 minimizing method is applied to seven-color UBVIJHK photometry by Fernandez-Soto, Lanzetta, & Yahil (1999). We use 187 template SEDs representing a wide variety of morphology and age of observed galaxies based on a population synthesis model by Kodama & Arimoto (1997). We introduce two new recipes. First, the amount of the internal absorption is changed as a free parameter in the range of E(B-V)=0.0 to 0.5 with an interval of 0.1. Second, the absorption due to intergalactic HI clouds is also changed by a factor of 0.5, 1.0, and 1.5 around the opacity given by Madau (1995). The total number of template SEDs is thus 187x6x3=3,366, except for the redshift grid. The dispersion sigma_z of our photometric redshifts with respect to spectroscopic redshifts is sigma_z=0.08 and 0.24 for z<2 and z>2, respectively, which are smaller than the corresponding values (sigma_z=0.09 and 0.45) by Fernandez-Soto et al. Improvement is significant, especially in z>2. This is due to smaller systematic errors which are largely reduced mainly by including three opacities due to intergalactic HI clouds. We discuss redshift distribution N(z) and cosmic star formation rate based on our new photometric redshifts.

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

New Improved Photometric Redshifts of Galaxies in the HDF 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 New Improved Photometric Redshifts of Galaxies in the HDF, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and New Improved Photometric Redshifts of Galaxies in the HDF will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-43838

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