CS 5-4 survey toward nearby IR bright galaxies

TL;DR

This survey of 24 infrared bright galaxies using CS 5-4 line observations reveals a strong correlation between dense gas tracers and infrared luminosity, emphasizing the role of dense gas in star formation.

Contribution

First comprehensive survey of CS 5-4 emission in nearby IR bright galaxies, establishing its correlation with infrared luminosity and star formation activity.

Findings

CS 5-4 emission detected in 14 out of 24 galaxies.

Strong correlation (coefficient 0.939) between CS 5-4 luminosity and IR luminosity.

Dense gas traced by CS 5-4 is closely linked to star formation in galaxies.

Abstract

With the observations of the CS 5-4 line toward a sample of 24 infrared bright galaxies using HHSMT, we detected CS 5-4 emission in 14 galaxies, including 12 ULIRGs/LIRGs and 2 nearby normal galaxies. As a good dense gas tracer, which has been well used for studying star formation in the Milky Way, CS 5-4 can trace the active star forming gas in galaxies. The correlation between CS 5-4 luminosity, which is estimated with detected CS 5-4 line emission, and infrared luminosity in these 14 galaxies is fitted with correlation coefficient of 0.939 and the slope close to unity. This correlation confirmed that dense gas, which is closely linked to star formation, is very important for understanding star formation in galaxies.