Dust Attenuation Curve for Local Subgalactic Star-forming Regions

Abstract

Abstract We compile a sample of about 157,000 spaxels from the Mapping Nearby Galaxies at the Apache Point Observatory (MaNGA) survey to derive the average dust attenuation curve for subgalactic star-forming regions of local star-forming galaxies (SFGs) in the optical wavelength, following the method of Calzetti et al. We obtain a -independent average attenuation curve for spaxels with 1.1 ≤ D n (4000) < 1.3, which is similar to the one derived from either local starbursts or normal SFGs. We examine whether and how the shape of the average attenuation curve changes with several local and global physical properties. For spaxels with 1.2 ≤ D n (4000) < 1.3, we find no dependence on either local or global physical properties for the shape of the average attenuation curve. However, for spaxels with younger stellar population (1.1 ≤ D n (4000) < 1.2), shallower average attenuation curves are found for star-forming regions with smaller stellar mass surface density, smaller star formation rate surface density, or those residing in the outer region of galaxies. These results emphasize the risk of using one single attenuation curve to correct the dust reddening for all type of star-forming regions, especially for those with fairly young stellar population.