Major and minor mergers: global star formation efficiency

MESA, VALERIA; MA. SOL ALONSO; DIEGO GARCÍA LAMBAS; ANA LAURA O'MILL

San Juan

Congreso; Reunión Anual de la Asociación Argentina de Astronomía; 2011

Instituto de Ciencias Astronómicas de la Tierra y el Espacio

We study galaxy pair samples selected from the Sloan Digital Sky Survey (SDSS-DR7) and we perform an analysis of minor and major mergers with the aim of investigating the dependence of galaxy properties on interactions. We build a galaxy pair catalog requiring r p < 25 kpc h-1 and V < 350 km s-1 within redshift z < 0.1. By visual inspection of SDSS images we removed false identifications and we classify the interactions into three categories: pairs undergoing merging, M; pairs with evident tidal features, T ; and non disturbed, N. We also divide the pair sample into minor and major interactions according to the luminosity ratio of the galaxy members. We conclude that the characteristics of the interactions and the ratio of lumi- nosity galaxy pair members involved in a merger are important parameters in setting galaxy properties.