The Fornax Deep Survey with VST. X. The assembly history of the bright
  galaxies and intra-group light in the Fornax A subgroup
  We present the study of the south-west group in the Fornax cluster centred on
the brightest group galaxy (BGG) Fornax A, observed as part of the Fornax Deep
Survey (FDS). This includes the analysis of the bright group members (mB < 16
mag) and the intra-group light (IGL). The main objective of this work is to
investigate the assembly history of the Fornax A group and to compare its
physical quantities as a function of the environment to that of the Fornax
cluster core. For all galaxies, we extract the azimuthally averaged surface
brightness profiles in three optical bands (g, r, i) by modelling the galaxy's
isophotes. We derive their colour profiles and structural parameters in all
respective bands. The long integration time and large covered area of the FDS
allow us to also estimate the amount of IGL. The majority of galaxies in the
Fornax A group are late-type galaxies (LTGs), spanning a range of stellar mass
of $8 < log (M_* M_{\odot}) < 10.5$. Six out of nine LTGs show a Type III
(up-bending) break in their light profiles, which is either suggestive of
strangulation halting star-formation in their outskirts or their HI-richness
causing enhanced star-formation in their outer-discs. The estimated luminosity
of the IGL is $6 \pm 2 \times 10^{10} L_{\odot}$ in g-band, which corresponds
to about 16% of the total light in the group. The Fornax A group appears to be
in an early stage of assembly with respect to the cluster core. The environment
of the Fornax A group is not as dense as that of the cluster core, with all
galaxies except the BGG showing similar morphology, comparable colours and
stellar masses, and Type III disc-breaks, without any clear trend of these
properties with group-centric distances. The main contribution to the IGL is
from the minor merging in the outskirts of the BGG NGC1316 and, probably, the
disrupted dwarf galaxies close to the group centre.
