We analyzed a catalog of 7,628 galaxies at 0 < z < 4 from CANDELS1 in the GOODS-South2 field in order to identify a sample of galaxy mergers and interactions. Galaxy mergers are believed to play a fundamental role in galaxy evolution. Developing methods to robustly and efficiently identify mergers becomes vital with our increasing ability to study mergers at higher redshifts and in larger samples. We explored merger identification based on visual morphology classification and preliminary attempts with automated quantitative methods. Using multiple detailed visual morphology classifications for each galaxy conducted by the CANDELS structure and morphology team, we created selection criteria to identify mergers from this visual classification catalog. We chose galaxies with high interaction classification and evidence of merger signatures (i.e. tidal features, double nuclei) to generate a catalog of 1051 galaxies we are confident are mergers. This represents a conservative sample of possible mergers. For comparison, we tested automated merger identification techniques previously used for lower redshift (z < 1) galaxies. This is one of the first large investigations of galaxy mergers at z > 1.
"Galaxy Merger Identification in the GOODS-South Field,"
Macalester Journal of Physics and Astronomy: Vol. 1
, Article 11.
Available at: https://digitalcommons.macalester.edu/mjpa/vol1/iss1/11