Local_Universe.GalGroup_Bayes table

The GalGroup_Bayes table contains data on galaxy groups/clusters that were found with Bayesian group finder based on marked/object point processes. The group/cluster identification numbers, groupid, are independent from id numbers in the GalGroup_2MRS and GalGroup_Comb tables.

Table structure

ColumnTypeUCDUnitDescription
groupidintmeta.id
meta.main
group/cluster identification number
ngalintmeta.numberrichness (number of members) of the group
raj2000doublepos.eq.radegright ascension of the group centre
dej2000doublepos.eq.decdegdeclination of the group centre
glondoublepos.galactic.londeggalactic longitude of the group centre
glatdoublepos.galactic.latdeggalactic latitude of the group centre
sglondoublepos.supergalactic.londegsupergalactic longitude of the group centre
sglatdoublepos.supergalactic.latdegsupergalactic latitude of the group centre
zcmbdoublesrc.redshiftCMB-corrected redshift of group, calculated as an average over all group/cluster members
groupdistdoublepos.distanceMpccomoving distance to the group centre
sigma_vfloatstat.stdev
phys.veloc
km/srms radial velocity deviation (sigma_v in physical coordinates)
sigma_skyfloatstat.stdev
pos.distance
Mpcrms deviation of the projected distance in the sky from the group centre (sigma_sky in physical coordinates); sigma_sky defines the extent of the group in the sky
r_maxfloatstat.max
phys.size.radius
Mpcdistance from group centre to the farthest group member in the plane of the sky
mass_200floatphys.mass10+12Msunestimated mass of the group assuming the NFW density profile
r_200floatphys.size.radiuskpcradius of the sphere in which the mean density of the group is 200 times higher than the average of the Universe
x_sgdoublepos.cartesian.xMpcsupergalactic Cartesian coordinate along the x-axis
y_sgdoublepos.cartesian.yMpcsupergalactic Cartesian coordinate along the y-axis
z_sgdoublepos.cartesian.zMpcsupergalactic Cartesian coordinate along the z-axis

Sample queries

  1. Select all columns for a specific group, based on the ID number groupid:
    SELECT * FROM Local_Universe.GalGroup_Bayes WHERE groupid=123
  2. Select all groups that have at least 5 galaxies:
    SELECT * FROM Local_Universe.GalGroup_Bayes WHERE ngal>=5