Access to Astronomical Catalogues

J/ApJS/107/201     The Stromlo-APM Redshift Survey IV     (Loveday+ 1996)
The Stromlo-APM Redshift Survey IV: The Redshift Catalogue
    Loveday J., Peterson B.A., Maddox S.J., Efstathiou G.
   <Astrophys. J. Suppl. Ser. 107, 201 (1996)>
   =1996ApJS..107..201L
ADC_Keywords: Galaxy catalogs; Photometry; Redshifts


Abstract:
    The Stromlo-APM Redshift Survey consists of 1797 galaxies with 
    b(J)<17.15 selected randomly at a rate of 1 in 20 from Automated Plate
    Measurement (APM) scans. The survey covers a solid angle of 1.3sr
    (4300 square degrees) in the south galactic cap. Redshifts have been
    measured for 1790 (99.6%) of the galaxies. The median galaxy recession
    velocity is 15,300 km/s and so the volume probed is approximately
    V=1.38 million Mpc3/h3.

File Summary:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
galaxy.dat        79     1797   Galaxies in Stromlo-APM survey
fields.dat        23      185   Field centres
holes.dat         75     1456   Holes drilled around big bright objects


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

   Bytes Format Units     Label       Explanations

   1- 11  A11   ---       ID          Galaxy name (1)
  14- 15  I2    h         RAh         Right Ascension 1950 (hours)
  17- 18  I2    min       RAm         Right Ascension 1950 (minutes)
  20- 24  F5.2  s         RAs         Right Ascension 1950 (seconds)
      27  A1    ---       DE-         Declination 1950 (sign)
  28- 29  I2    deg       DEd         [17,72] Declination 1950 (degrees)
  31- 32  I2    arcmin    DEm         Declination 1950 (arcminutes)
  34- 37  F4.1  arcsec    DEs         Declination 1950 (arcseconds)
  40- 44  F5.2  mag       Bj          Bj magnitude
  47- 49  I3    arcsec    MajDiam     Major diameter
  52- 54  I3    arcsec    MinDiam     Minor diameter
  57- 59  I3    deg       PA          [0,360[ Position angle (degrees) (2)
  63- 64  I2    ---       MType       Morphological type (3)
  67- 71  I5    km/s      RV          Radial velocity (heliocentric)
  74- 76  I3    km/s      e_RV        Error in radial velocity
  78- 79  I2    ---       r_RV        Source of radial velocity (4)

Note (1):
    Each galaxy name is composed of the survey field number and the x, y
    position of the galaxy on the plate---this should ease location of any
    particular galaxy on the plate material. The first 3 digits are the
    SERC field number. The second set of digits are the x-position in
    millimetres from the centre of the plate (actually the APM scan
    centre). These are preceded by a `+' sign for galaxies to the right
    (west) of the plate centre or by a `-' sign for galaxies to the left
    (east) of centre. The final 3 digits are the y position, again in mm
    from the plate centre. A preceding `-' indicates galaxies above
    (north) of the plate centre, `+' indicates galaxies below (south) of
    the centre.
Note (2):
    PA is measured clockwise from south-north line.
Note (3):
    The morphological type is given by mod(Mtype,10)
    1 = Elliptical
    2 = Lenticular
    3 = Spiral
    4 = Irr/Pec
    5 = Uncertain
    8 = Merged with star
    9 = Multile galaxy
    Galaxies from the ESO catalogue have 10 added, those assigned
    morphological types by SJM have 20 added (all others typed by JL).
Note (4):
    The RV_src flag indicates the source of the radial velocity:
   -1 = unreliable
    0 = not available
    1 = MSSSO 2.3m, absorption features
    2 = MSSSO 2.3m, emission lines
    3 = MSSSO 2.3m, both absorption and emission
    4 = Southern Sky Redshift Survey
    5 = Dressler & Schectman 1988AJ.....95..284D
    6 = Huchra's ZCAT (Cat. VII/193) compilation


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

   Bytes Format Units   Label       Explanations

   1-  3  I3    ---     Field       [53,605] SERC field number (1)
   5- 10  F6.2  deg     RAdeg       RA  of field centre 1950 (degrees)
  12- 17  F6.2  deg     DEdeg       Dec of field centre 1950 (degrees)
  19- 23  F5.3  deg     RAextent    RA extent of field (degrees)

Note (1): This table lists SERC field centres in 1950 decimal degrees.
    The column labeled RAextent gives the half-size of the Right Ascension
    of the field in degrees. The DEextent is 2.5 degrees for every field.
    This list of fields may be used for example to generate a random
    catalogue with the same boundaries as the survey data as follows.

    A point with coordinates (RAp, DEp) is inside a field with coordinates
    (RAf, DEf) if (abs(RAp - RAf) < RAextent) and (abs(DEp - DEf) <
    DEextent). An additional test should be made to allow for the extra
    overlap between fields at RA = 0. If RAf is not zero then abs(RAp)
    must be greater than RAextent.


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

   Bytes Format Units    Label       Explanations

   1-  3  I3    ---      Field       [53,605] SERC field number (1)
   5- 15  F11.7 deg      HOLX1       RA  of 1st corner of hole (degrees)
  17- 27  F11.7 deg      HOLY1       Dec of 1st corner of hole (degrees)
  29- 39  F11.7 deg      HOLX2       RA  of 2nd corner of hole (degrees)
  41- 51  F11.7 deg      HOLY2       Dec of 2nd corner of hole (degrees)
  53- 63  F11.7 deg      HOLX3       RA  of 3rd corner of hole (degrees)
  65- 75  F11.7 deg      HOLY3       Dec of 3rd corner of hole (degrees)

Note (1):
    This table lists the coordinates of parallelogram shaped holes drilled
    out around big bright objects in the survey. The following FORTRAN
    code will test if a point with coordinates (xr,yr) lies in a hole.


Fortran program to use the holes.dat file:
c
c *** Set drilled =  .true. if point (xr,yr) lies in a given hole
c
c     Method: Express displacement vector to (xr,yr) in terms of basis
c     vectors of parallelogram
c
c       Vr = a1*V1 + a2*V2
c       -       -       -
c
c     Then (xr,yr) is drilled if  0 ≤ a1,a2 ≤ 1
c
c     First, ensure that the RA coords are in [-180,180], since the APM
c     survey straddles RA = 0.
c
      if (xr.gt.180.0) xr = xr - 360.0

      drilled = .false.
      dx = xr - HOLX1
      dy = yr - HOLY1
      dx1 = HOLX2 - HOLX1
      dy1 = HOLY2 - HOLY1
      dx2 = HOLX3 - HOLX1
      dy2 = HOLY3 - HOLY1

      if (abs(dx2).gt.0) then
         a1 = (dx*dy2 - dy*dx2)/(dx1*dy2 - dy1*dx2)
         a2 = (dx - a1*dx1)/dx2
         if (0.le.a1.and.a1.le.1.and.0.le.a2.and.a2.le.1) drilled = .true.
      endif

References:
    Loveday et al., Paper I.      1992ApJ...390..338L
    Loveday et al., Paper II.     1995ApJ...442..457L
    Loveday et al., Paper III.    1996ApJ...468....1L
(End)       Jon Loveday [Fermilab]                                   24-Apr-1996