As part of the Fornax Deep Survey with the ESO VLT Survey Telescope , we present new g and r bands mosaics of the SW group of the Fornax cluster .
It covers an area of 3 \times 2 Â square degrees around the central galaxy NGCÂ 1316 .
The deep photometry , the high spatial resolution of OmegaCam and the large covered area allow us to study the galaxy structure , to trace stellar halo formation and look at the galaxy environment .
We map the surface brightness profile out to 33Â arcmin ( \sim 200 Â kpc \sim 15 R _ { e } ) from the galaxy centre , down to \mu _ { g } \sim 31 Â mag arcsec ^ { -2 } and \mu _ { r } \sim 29 Â mag arcsec ^ { -2 } .
This allow us to estimate the scales of the main components dominating the light distribution , which are the central spheroid , inside 5.5Â arcmin ( \sim 33 Â kpc ) , and the outer stellar envelope .
Data analysis suggests that we are catching in act the second phase of the mass assembly in this galaxy , since the accretion of smaller satellites is going on in both components .
The outer envelope of NGCÂ 1316 still hosts the remnants of the accreted satellite galaxies that are forming the stellar halo .
We discuss the possible formation scenarios for NGCÂ 1316 , by comparing the observed properties ( morphology , colors , gas content , kinematics and dynamics ) with predictions from cosmological simulations of galaxy formation .
We find that i ) the central spheroid could result from at least one merging event , it could be a pre-existing early-type disk galaxy with a lower mass companion , and ii ) the stellar envelope comes from the gradual accretion of small satellites .