Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-05-31
Astron.J.122:1104,2001
Astronomy and Astrophysics
Astrophysics
48 pages, 15 figures
Scientific paper
10.1086/322093
We present bright galaxy number counts in five broad bands ($u', g', r', i', z'$) from imaging data taken during the commissioning phase of the Sloan Digital Sky Survey (SDSS). The counts are derived from two independent stripes of imaging scans along the Celestial Equator, one each toward the North and the South Galactic cap, covering about 230 and 210 square degrees, respectively. A careful study is made to verify the reliability of the photometric catalog. For galaxies brighter than $r^* = 16$, the catalog produced by automated software is examined against eye inspection of all objects. Statistically meaningful results on the galaxy counts are obtained in the magnitude range $12 \le r^* \le 21$, using a sample of 900,000 galaxies. The counts from the two stripes differ by about 30% at magnitudes brighter than $r^*= 15.5$, consistent with a local $2\sigma$ fluctuation due to large scale structure in the galaxy distribution. The shape of the number counts-magnitude relation brighter than $r^* = 16$ is well characterized by $N \propto 10^{0.6m}$, the relation expected for a homogeneous galaxy distribution in a ``Euclidean'' universe. In the magnitude range $ 16 < r^* < 21$, the galaxy counts from both stripes agree very well, and follow the prediction of the no-evolution model, although the data do not exclude a small amount of evolution. We use empirically determined color transformations to derive the galaxy number counts in the $B$ and $I_{814}$ bands. We compute the luminosity density of the universe at zero redshift in the five SDSS bands and in the $B$ band. We find ${\cal L}_{B} = 2.4 \pm 0.4 \times 10^8L_\odot h $Mpc$^{-3}$, for a reasonably wide range of parameters of the Schechter luminosity function in the $B$ band.
collaboration SDSS
Fukugita Masataka
Hogg David Wardell
Ivezic Zeljko
Kim Rita S. J.
No associations
LandOfFree
Galaxy Number Counts from the Sloan Digital Sky Survey Commissioning Data 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 Number Counts from the Sloan Digital Sky Survey Commissioning Data, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Galaxy Number Counts from the Sloan Digital Sky Survey Commissioning Data will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-249944