Detection of CO(J=1-0) Emission from Barred Spiral Galaxies at z~0.1

TL;DR

This study detects CO emission in nine barred spiral galaxies at z~0.1, revealing their star formation activity and molecular gas content, and providing new insights into galaxy evolution at intermediate redshifts.

Contribution

First CO detection survey of barred spiral galaxies at z~0.1, showing their molecular gas properties and star formation efficiency compared to local galaxies.

Findings

Six out of nine galaxies detected in CO emission.

Detected galaxies are IR dimmest at z~0.1 with high L_CO' and L_IR.

Star formation efficiency is comparable or slightly higher than local spirals.

Abstract

We present the results of CO (J=1-0) observations towards nine barred spiral galaxies at z=0.08-0.25 using the 45-m telescope at Nobeyama Radio Observatory (NRO). This survey is the first one specialized for barred spiral galaxies in this redshift range. We detected CO emission from six out of nine galaxies, whose CO luminosity (L_CO') ranges (1.09-10.8)\times10^9 K km s^{-1} pc^2. These are the infrared (IR) dimmest galaxies that have ever been detected in CO at z~0.1 to date. They follow the L_CO'-L_IR relation among local spiral galaxies, Luminous Infrared Galaxies (LIRGs), Ultra-Luminous Infrared Galaxies (ULIRGs) and Sub-millimeter Galaxies (SMGs). Their L_CO' and L_IR are higher than that of local spiral galaxies which have been detected in CO so far, and L_IR/L'_CO, which is a measure of star formation efficiency, is comparable to or slightly higher than that of local ones. This result suggests that these galaxies are forming stars more actively than local spirals galaxies simply because they have more fuel.