Physical Galaxy Pairs and Their Effects on Star Formation

TL;DR

This study analyzes 776 galaxy pairs to understand how physical interactions influence star formation, finding that truly interacting pairs exhibit higher star formation rates than apparent pairs, highlighting the role of matter exchange.

Contribution

It provides a detailed comparison of star formation activity between truly physical and optical galaxy pairs, emphasizing the impact of physical interactions on star formation enhancement.

Findings

Truly physical galaxy pairs show higher star formation rates.

Star formation activity is likely driven by matter exchange between companions.

Physical interactions significantly trigger star formation.

Abstract

We present 776 truly physical galaxy pairs, 569 of them are close pairs and 208 false pairs from Karachentsev (1972) and Reduzzi & Rampazzo (1995) catalogues, which contains 1012 galaxy pairs. Also we carried out star formation activity through the far-infrared emission (FIR) in physical (truly) interacting galaxies in some galaxy pairs and compared them with projection (optical) interacting galaxy pairs. We focused on the triggering of star formation by interactions and analyzed the enhancement of star formation activity in terms of truly physical galaxy pairs. The large fraction of star formation activity is probably due to the activity in the exchange of matter between the truly companions. The star formation rate (SFR) of galaxies in truly galaxy pairs is found to be more enhanced than the apparent pairs.