Statistical study of M 51-type galaxies

We present a statistical analysis of a new sample of M 51-type galaxies. Us ing the MCG and VV catalogues, we selected 32 such binary systems. We found that a typical M 51-type pair consists of a bright L* spiral galaxy and a satellite with blue luminosity 1/30-1/3 of the primary one. The main galaxi es in such pairs are often barred and have two well-defined spiral arms. M 51-type systems show an enhanced star formation rate (from FIR luminosities ). We found a weak dependence of the star formation rate of the system on r elative luminosity of the companion. M 51-type galaxies are relatively freq uent: about 1/12 of all pairs are of M 51-type.