Investigating merging galaxies by using Pan-STARRS images

Abstract

Aims. We studied the r′-, z′-, and y′-band images of merging galaxies from the observations of the Panoramic Survey Telescope & Rapid Response System (Pan-STARRS). The merging galaxies were selected from our merging catalog that was created by checking the images of the Red-Sequence Cluster Survey 2 from the observations of the Canada France Hawaii Telescope. Methods. By using the homomorphic-aperture, we determined the photometric results of these merging systems. To obtain accurate photometry, we calibrated the Pan-STARRS r′-, z′-, and y′-band data to match the results of Sloan Digital Sky Survey Data Release 9. We also investigated the stellar masses of the merging galaxies by comparing the Wide-field Infrared Survey Explorer 3.4 μm emission with the calibrated y′-band data. Results. We present a catalog of the r′-, z′-, and y′-band photometric results for 4698 merging galaxies. For extended sources, our results suggest that the homomorphic-aperture method can obtain more reasonable results than the Desktop Virtual Observatory photometry. We derived new relations between the Pan-STARRS y′-band luminosities and the stellar masses of the merging galaxies. Our results show that the stellar masses of the merging galaxies range from 108 to 1013M⊙; some of the dry mergers could be as massive as 1013M⊙.