The Spitzer-IRAC/MIPS Extragalactic Survey (SIMES): II enhanced nuclear
  accretion rate in galaxy groups at z$\sim$0.2
  For a sample of star forming galaxies in the redshift interval
0.15$<$z$<$0.3, we study how both the relative strength of the AGN infra-red
emission, compared to that due to the star formation (SF), and the numerical
fraction of AGNs, change as a function of the total stellar mass of the hosting
galaxy group (M$^{*}_{\mathrm{group}}$), between $10^{10.25}$ and
$10^{11.9}$M$_{\odot}$. Using a multi-component SED fitting analysis, we
separate the contribution of stars, AGN torus and star formation to the total
emission at different wavelengths. This technique is applied to a new
multi-wavelength data-set in the SIMES field (23 not redundant photometric
bands), spanning the wavelength range from the UV (GALEX) to the far-IR
(Herschel) and including crucial AKARI and WISE mid-IR observations (4.5 \mu
m$<\lambda<$24 \mu m), where the BH thermal emission is stronger. This new
photometric catalog, that includes our best photo-z estimates, is released
through the NASA/IPAC Infrared Science Archive (IRSA). Groups are identified
through a friends of friends algorithm ($\sim$62% purity, $\sim$51%
completeness). We identified a total of 45 galaxies requiring an AGN emission
component, 35 of which in groups and 10 in the field. We find BHAR$\propto
($M$^{*}_{\mathrm{group}})^{1.21\pm0.27}$ and (BHAR/SFR)$\propto
($M$^{*}_{\mathrm{group}})^{1.04\pm0.24}$ while, in the same range of
M$^{*}_{\mathrm{group}}$, we do not observe any sensible change in the
numerical fraction of AGNs. Our results indicate that the nuclear activity
(i.e. the BHAR and the BHAR/SFR ratio) is enhanced when galaxies are located in
more massive and richer groups.
