Oral Presentation

The Correlation of Star Formation in Galaxies with Neighbors

Jun-Sung Moon (Yonsei University), Suk-Jin Yoon (Yonsei University)

We investigate the impact of neighboring galaxies on recent star formation rate (SFR) of Sloan Digital Sky Survey galaxies. Our sample galaxies are matched with their most influential neighbors, and their UV + optical colors and Hα emission are compared along neighbor's morphology and distance to the neighbor. In particular, through the comparison with a isolated control sample which is matched in terms of morphology, luminosity, redshift, and large-scale environment, we could show pure effects of neighbors without any confusion with large-scale environmental effects on galaxies' properties. The results suggest that the SFR of SDSS galaxies is affected by their interacting neighbor’s properties. Concretely speaking, late-type galaxies accompanying late-type neighbors tends to show enhanced SFR compared to the isolated group, while those with early-type neighbors has statistically redder colors than the isolated group. We will discuss detailed phenomena and possible mechanisms to explain our results.