Sdss Dr7 Interacting Galaxies Sample Selection And Analysis Of The Nature Of Particular Average

Galaxy interactions play an important role in understanding thegalaxy formation and evolution. We have presented a large sample ofpair galaxies from the SDSS DR7by using the selection criteriadeveloped by Ellison et al.（2008） and Patton et al.（2010）. The number is16,363with the stellar mass ratio between0.1and10, relative velocitylower than500km/s and projected separation lower than80h^-1₇₀kpc.The effect of galaxy interactions on the star-formation activities isinvestigated. We find that interaction between early-type, mixedmerging galaxies does not enhance significant star formation activitywhile it does for late-type merging galaxies. And we also research onthe relation between the Specific star formation rate（SSFR） and find thatthe SSFR decreases with separation increasing. The SSFR of pair galaxieswhose mass ratio is similar is greater than the ones are different.The layout of the paper is as follows. In chapter2we describe theresearch history of interacting and merging galaxies. In chapter3weshow the original of the data used in the paper and introduce how toacquire our merging galaxy sample. In chapter4, we discuss theproperties of merging galaxies and give the discussion in chapter5.