Abstract
We study the spatially-resolved star formation rates of 1494 galaxies in the
SDSSIV-MaNGA Survey. Star formation rates are calculated using a two-step
process, exploiting H$_\alpha$ in star-forming regions and $D_n4000$ in zones
identified as AGN/LI(N)ER or lineless according to the BPT diagram. This
enables a complete view of how radial profiles of specific star formation rate
depend on stellar mass, galaxy structure and environment, providing valuable
clues about the nature of both secular and environmental quenching processes.
We report on the existence of `Centrally Suppressed' galaxies, which have lower
SSFR in their cores compared to their disks. The profiles of centrally
suppressed and unsuppressed galaxies are distributed in a bimodal way, with
very few galaxies having intermediate profile shapes. Galaxies with large
stellar masses and central velocity dispersions are much more likely to be
centrally-suppressed than low-mass galaxies, a result linked to their
morphology and the presence of AGN/LI(N)ER like emission. Centrally suppressed
galaxies also display lower star formation at all radii compared to
unsuppressed galaxies. Independent of galaxy type, galaxies identified as
satellites in larger dark matter halos have noticeably lower SSFR at outer
radii compared to central galaxies. This uniform suppression could be a signal
of the stripping of hot gas reservoirs through a process like strangulation. We
find that satellites are not more likely to be suppressed in their cores than
centrals, indicating that core suppression is an entirely secular process. We
find no secondary correlation between the local environment density and the
profiles of star formation rate surface density.
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