Estimating the evolution and the content fractions of baryonic gas for Luminous Infrared Galaxies

TL;DR

This study analyzes 82 Luminous Infrared Galaxies to understand their gas content, evolution, and star formation processes, revealing correlations between gas fractions, dust, and galaxy properties.

Contribution

It provides new insights into the relationship between gas fractions, dust, and galaxy evolution in LIRGs using multi-source data analysis.

Findings

Higher gas fractions correlate with less efficient star formation.

Gas exhaustion time decreases with increasing stellar mass.

Gas depletion time increases with baryonic gas mass fraction.

Abstract

Luminous Infrared Galaxies (LIRGs) play a crucial role in understanding of galaxy evolution. The present study examined 82 LIRGs, using data taken from the Sloan Digital Sky Survey (SDSS), NASA/IPAC Extragalactic Database (NED), and HyperLEDA to explore their gas fractions and optical properties. The analysis of data highlights the relationship between molecular-to-atomic mass of hydrogen gas ratio MH2/MH1 and morphological types, gas mass fractions, and galaxy characteristics such as color and luminosity. The results showed that the regressions between Mdust - M*,V and Mdust - SFR are not quite flat (when correlation coefficient > 0.5), which indicates a decrease in the dust-to-stellar content ratio as the gas is consumed and transformed into stars, and also a relatively flat trend for M dust - M*,V and fdust,bar - M*,V. Moreover, as the star mass declines, the total gas mass fraction (fgas) increases quickly, with a high negative correlation coefficient of - 0.7 and a regression of - 0.85. Therefore, it can be inferred that galaxies with a high gas fraction (fgas) are either accreting gas at a rate sufficient to meet their energy requirements for star formation or converting gas into stars less effectively. According to the findings, the gas exhaustion time in these galaxies quickly reduces as the stellar mass increases, with a significant negative correlation coefficient of - 0.7 and a regression that is a nearly linear regression of - 0.9. On the other hand, when the baryonic gas mass fraction grows, which makes up the majority of the baryonic gas, grows, the gas depletion time increases quickly.