ALMA ACA CO Observations in Isolated Galaxy Pairs: the Low Mass Picture

Analyses of pair galaxy interactions provide a critical picture of dynamics influencing gas and stellar buildup in low-mass, metal-poor environments. Previous probing of low-redshift TiNY Titans dwarf galaxy pairs (10$^{7}$ M$_{\odot}$ $<$ M $<$ 10$^{9.7}$ M$_{\odot}$; 8.0 $<$ Z $<$ 8.9) via the Sloan Digital Sky Survey found enhanced star formation rates with separation distances R$_{sep}$ $<$ ~100 kpc. Whether this star formation is a result of an increased H$_{2}$ mass or efficiency in which the H$_{2}$ is converted to stars remains unclear. For the first time, we present ALMA Atacama Compact Array molecular gas quantities of these dwarf galaxy pair systems with close separations (6 kpc $<$ R$_{sep}$ $<$ 48 kpc) via the CO tracer. CO is detected in four galaxies, and an application of the Milky Way accepted $\alpha_{CO}$ results in molecular gas calculations of ~10$^{8}$ M$_{\odot}$. A comparison of molecular gas and stellar formation rate to the xCOLDGASS (10$^{9}$ M$_{\odot}$ $<$ M $<$ 10$^{11.5}$ M$_{\odot}$) data set does not identify higher H$_{2}$ nor efficiency in these dwarfs. This preliminary study thus demonstrates the feasibility of measuring H$_{2}$ reservoirs in dwarfs, with future studies aimed at constraining molecular gas mass at lower metallicity environments.