Hickson Compact Groups of Galaxies (HCG) Catalog

Each group contains four or more galaxies, has an estimated mean surface brightness brighter than 26.0 magnitude per arcsec<sup>2</sup> and satisfies an isolation criterion. Dynamical parameters which were derived for 92 of the 100 groups are also included in the database.

(Note that the Hubble constant was assumed to be Ho = 100 km/s/Mpc.) This database table essentially contains the information given in Table 1 of Hickson, P. (1982, ApJ, 255, 382) and Table 3 of Hickson, P. et al. (1992, ApJ, 399, 353). Consequently, the information on individual galaxies in the Hickson groups that is also given in these references, e.g., in Table 2 of Hickson, P. et al. (1992, ApJ, 399, 353), is not in the HCG database table; however, the latter data can be found in the related HEASARC database table HCGGALAXY.