Galaxy Star-Formation as a Function of Environment in the Early Data Release of the Sloan Digital Sky Survey

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Accepted for publication in ApJ, 24 pages in emulateapj.sty

Scientific paper

10.1086/345593

(Abridged) We present in this paper a detailed analysis of the effect of environment on the star-formation activity of galaxies within the EDR of the SDSS. We have used the Halpha emission line to derive the star-formation rate (SFR) for each galaxy within a volume-limited sample of 8598 galaxies with 0.05 < z < 0.095 and M(r)<= -20.45. We find that the SFR of galaxies is strongly correlated with the local (projected) galaxy density and thus we present here the density-SFR relation that is analogous to the density-morphology relation. The effect of density on the SFR of galaxies is seen in three ways. First, the overall distribution of SFRs is shifted to lower values in dense environments compared with the field population. Second, the effect is most noticeable for the strongly star-forming galaxies in the 75th percentile of the SFR distribution. Third, there is a ``break'' (or characteristic density) in the density-SFR relation at a local galaxy density of 1h-2 Mpc-2. To understand this break further, we have studied the SFR of galaxies as a function of clustercentric radius from 17 clusters and groups objectively selected from the SDSS EDR data. The distribution of SFRs of cluster galaxies begins to change, compared with the field population, at a clustercentric radius of 3-4 virial radii, which is consistent with the characteristic break in density that we observe in the density-SFR relation. Our tests suggest that the density-morphology relation alone is unlikely to explain the density-SFR relation we observe. Taken all together, these works demonstrate that the decrease in SFR of galaxies in dense environments is a universal phenomenon over a wide range in density (from 0.08 to 10h-2 Mpc-2) and redshift (out to z = 0.5).

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

Galaxy Star-Formation as a Function of Environment in the Early Data Release of the Sloan Digital Sky Survey 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 Galaxy Star-Formation as a Function of Environment in the Early Data Release of the Sloan Digital Sky Survey, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Galaxy Star-Formation as a Function of Environment in the Early Data Release of the Sloan Digital Sky Survey will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-204224

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