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Description
We present an all-sky catalogue of 395 nearby galaxy groups revealed in the Local Supercluster and its surroundings. The groups and their associations are identified among 10914 galaxies at |b|>15{deg} with radial velocities V_LG_<3500km/s. Our group-finding algorithm requires the group members to be located inside their zero-velocity surface. Hereby, we assume that individual galaxy masses are proportional to their total K-band luminosities, M/L_K_=6M_{sun}_/L_{sun}_. The sample of our groups, where each group has n>=4 members, is characterized by the following medians: mean projected radius <R>=268kpc, radial velocity dispersion {sigma}_V_=74km/s, K-band luminosity L_K_=1.2x10^11^L_{sun}_, virial and projected masses M_vir_=2.4x10^12^ and M_p_=3.3x10^12^M_{sun}_, respectively. Accounting for measurement error reduces the median masses by 30 per cent. For 97 per cent of identified groups the crossing time does not exceed the cosmic time, 13.7Gyr, with the median at 3.8Gyr. We examine different properties of the groups, in particular of the known nearby groups and clusters in Virgo and Fornax. About a quarter of our groups can be classified as fossil groups where the dominant galaxy is at least 10 times brighter than the other group members.
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