Correlation between Dust Attenuation and Star Formation Timescales in Nearby Galaxies
Rafli Rizaldi (a*), Muhammad Fathir Rizqy Fadli (a), Luvena Yumi Odelia (a), Dian P. Triani (b)

a) Astronomy Study Program, Faculty of Mathematics and Natural Sciences, ITB
*raflirizaldigamer[at]gmail.com
b) Center for Astrophysics, Harvard & Smithsonian

Abstract

The dust content in galaxies is a key indicator of star formation processes and galactic evolution. In high-redshift galaxies, there^s a strong anti-correlation between dust attenuation \(A_V\) and specific star formation rate \(sSFR\), likely driven by dust from core-collapse supernovae. In contrast, nearby galaxies have had more time for dust to form through other channels, like AGB stars and grain growth. This study will investigate whether the \(A_V-1/sSFR\) relation still holds in the local Universe. Using data from SDSS DR19 for a sample of nearby galaxies \(\left(z < 0.1\right)\), we derive the dust attenuation \(\left(A_V\right)\) from Balmer decrement \(\left(H\alpha/H\beta\right)\). Star formation rates \(\left(SFR\right)\) are estimated from dust-corrected \(H\alpha\) luminosities, while stellar masses \(\left(M_*\right)\) are calculated from galaxy photometry. From these parameters, we calculate the \(sSFR\) \(\left(SFR/M_*\right)\) for each galaxy. This allows us to map the \(A_V-1/sSFR\) relation, and compare it to the expectations based on different dust formation mechanisms.

Keywords: Dust attenuation- Specific star formation rate- Balmer decrement

Topic: Galaxies and Cosmology