We investigate how star formation quenching proceeds within central and
satellite galaxies using spatially resolved spectroscopy from the SDSS-IV MaNGA
DR15. We adopt a complete sample of star formation rate surface densities
(ΣSFR), derived in Bluck et al. (2020), to compute the distance
at which each spaxel resides from the resolved star forming main sequence
(ΣSFR−Σ∗ relation): ΔΣSFR. We study
galaxy radial profiles in ΔΣSFR, and luminosity weighted
stellar age (AgeL), split by a variety of intrinsic and environmental
parameters. Via several statistical analyses, we establish that the quenching
of central galaxies is governed by intrinsic parameters, with central velocity
dispersion (σc) being the most important single parameter. High mass
satellites quench in a very similar manner to centrals. Conversely, low mass
satellite quenching is governed primarily by environmental parameters, with
local galaxy over-density (δ5) being the most important single
parameter. Utilising the empirical MBH - σc relation, we estimate
that quenching via AGN feedback must occur at MBH≥106.5−7.5M⊙, and is marked by steeply rising ΔΣSFR radial
profiles in the green valley, indicating `inside-out' quenching. On the other
hand, environmental quenching occurs at over-densities of 10 - 30 times the
average galaxy density at z∼0.1, and is marked by steeply declining
ΔΣSFR profiles, indicating `outside-in' quenching. Finally,
through an analysis of stellar metallicities, we conclude that both intrinsic
and environmental quenching must incorporate significant starvation of gas
supply.ERC
STF