Compact Groups of Galaxies selected by stellar mass: The 2MASS Compact
  Group Catalogue
  We present a photometric catalogue of compact groups of galaxies (p2MCGs)
automatically extracted from the 2MASS extended source catalogue. A total of
262 p2MCGs are identified, following the criteria of Hickson (1982), of which
230 survive visual inspection. Only 1/4 of these groups were previously known
compact groups (CGs). Among the 144 p2MCGs that have all their galaxies with
known redshifts, 85 have 4 or more accordant galaxies. This v2MCG sample of
velocity-filtered p2MCGs constitutes the largest sample of CGs catalogued to
date, with both well-defined selection criteria and velocity filtering, and is
the first CG sample selected by stellar mass. We compared the properties of the
78 v2MCGs with <v> > 3000 km/s with the properties of other CG samples, as well
as those (mvCGs) extracted from the semi-analytical model of Guo et al. (2011)
run on the high-resolution Millennium-II simulation. In this mvCG sample, 2/3
of the groups are physically dense. The space density of v2MCGs within 6000
km/s is 4 times that of the Hickson sample up to the same distance and with the
same criteria used here, but still 40% less than that of mvCGs. The v2MCG
constitutes the first group catalogue showing statistically significant signs
of wide magnitude gaps (according to Tremaine-Richstone statistics) and
centrally located 1st-ranked galaxies, both consistent with the predictions
obtained from mvCGs. By virtue of its automatic selection with the popular
Hickson criteria, its size, its selection on stellar mass, and its statistical
signs of mergers and centrally located brightest galaxies, the v2MCG catalogue
appears to be the laboratory of choice to study compact groups of 4 or more
galaxies of comparable luminosity. [Abridged]
