The AstroSat UV Deep Field North: The IRX- relation for the UV-selected galaxies at z 0. 5-0. 7

The relation between the observed UV continuum slope () and the infrared excess (IRX) is used as a powerful probe to understand the nature of dust attenuation law in high-redshift galaxies. We present a study of 83 UV-selected galaxies between redshift 0. 5 and 0. 7 from the AstroSat UV Deep Field north (AUDFn) that encloses the GOODS-north field. Using empirical relation, we estimate the observed IRX of 52 galaxies that are detected in either one or both of the Herschel PACS 100m and 160m bands. We further utilize the multi-band photometric data in 14 - 18 filters from the UVIT, KPNO, HST, Spitzer, and Herschel telescopes to perform spectral energy distribution (SED) modeling. Both the observed and model-derived IRX - values show a large scatter within the span of previously known relations, signifying diversity in dust attenuation. We found a distinct relation between the best-fit power law slope of the modified Calzetti relation () in the IRX - plane: where the steeper SMC-like attenuation law prefers lower values. Our SED model based IRX - relation shows a preference for steeper SMC-like attenuation which we further confirm from the agreement between extinction-corrected star formation rates derived using H emission line and the observed FUV plus reprocessed far-IR fluxes. The current study reveals a strong positive correlation between IRX and the galaxy stellar mass between 10^9. 5 and 10^11. 0 M_, signifying increased dust production in more massive star-forming galaxies.