2MASS/SDSS CLOSE MAJOR-MERGER GALAXY PAIRS

We select a close major-merger candidate galaxy pair sample in order to calculate the K-s luminosity function (LF) and pair fraction representative of the merger/interaction component of galaxy evolution in the local universe. The pair sample (projected separation 5 h(-1) kpc <= r <= 20 h(-1) kpc, K-s-band magnitude difference Delta K-s <= 1 mag) is selected by combining the Two Micron All Sky Survey (2MASS) with the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5). The resulting data set contains 340 galaxies covering 5800 deg(2). A stellar mass function is also translated from the LF. A differential pair fraction displays nearly constant fraction of galaxy pairs as a function of galaxy mass from 10(9) to 10(11.5) M-circle dot. The differential pair fraction is less subject to absolute magnitude bias due to survey limitations than the standard total pair fraction. These results suggest that major-merger candidate pairs in the 0< z < 0.1 universe are developed from similar to 1.6% of the galaxy population without dependence on galaxy mass for pair components below 10(11) M-circle dot. The derived LF combined with merger model timescales give local merger rates per unit volume which decrease with masses greater than 10(11) M-circle dot.