Access to Astronomical Catalogues

VII/204             Galaxy properties at NGP (Odewahn+ 1995)
Galaxy properties at the North Galactic Pole.
I. Photometric properties on large spatial scales.
       Odewahn S.C., Aldering G.
      <Astron. J. 110, 2009 (1995)>
      =1995AJ....110.2009O      (SIMBAD/NED BibCode)
ADC_Keywords: Galaxy catalogs ; Magnitudes


Abstract:
    A two-color study  of the galaxies  detected on POSS-I  in a 289deg2
    region centered  on the  North Galactic  Pole is  presented. We  use a
    variety  of mapping techniques to characterize the large-scale spatial
    distribution of galaxies. The depth and sample size of this new survey
    allows, for  the  first  time,  the  isolation  of  large  photometric
    subsamples  of galaxies in  high- and low-density  environments on the
    scale of superclusters.  Our  principal  finding  is  a  statistically
    significant difference between  the  mean  photometric  properties  of
    these  subsamples in the sense that  galaxies in the high-density Coma
    and  filament environments have redded colors and larger concentration
    indices than  galaxies drawn  from low-density  interfilament regions.
    These results are  in  agreement  with  the  known  morphology-density
    relation.

File Summary:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
catalog.dat       58    36402   All APS-measured galaxies with Omag ≤ 20.0
                                  (NGP9)


Byte-by-byte Description of file: catalog.dat

   Bytes Format Units   Label     Explanations

   1-  7  I7    ---     No        Object number (unique within a plate)
   9- 11  I3    ---     POSS-I    POSS-I plate number (see catalog VI/25)
  13- 14  I2    h       RAh       Right ascension (1950)
  16- 17  I2    min     RAm       Right ascension (1950)
  19- 23  F5.2  s       RAs       Right ascension (1950)
      25  A1    ---     DE-       Declination sign
  26- 27  I2    deg     DEd       Declination (1950)
  29- 30  I2    arcmin  DEm       Declination (1950)
  32- 35  F4.1  arcsec  DEs       [0/60] Declination (1950)
  37- 41  F5.2  mag     Omag      O isophotal magnitude (threshold about
                                    24.5 mag/arcsec2 in B)
  43- 47  F5.2  mag     O-E       O-E color
  49- 52  F4.2  ---     C31      *C31 concentration index
  54- 58  F5.1  arcsec  Diam      Isophotal (equivalent) diameter

Note on C31: this index is the ratio between the radius
     with 75% and 25% of the isophotal light.


History: Copied on 18-Nov-1996 from
   http://groucho.la.asu.edu/~sco/sco1/data/data.html
(End)                                     Francois Ochsenbein [CDS]  18-Nov-1996