Dust Attenuation Curve for Local Subgalactic Star-forming Regions
  We compile a sample of about 157,000 spaxels from the Mapping Nearby Galaxies
at the Apache Point Observatory 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 \cite{Calzetti1994}.
We obtain a $D_n(4000)$-independent average attenuation curve for spaxels with
$1.1\leq D_n(4000)<1.3$, 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 $1.2\leq D_n(4000)<1.3$, 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 ($1.1\leq D_n(4000)<1.2$),
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 types of star-forming regions, especially for those with
fairly young stellar population.
