Early-type galaxies in the Antlia Cluster: A deep look into scaling
  relations
  We present the first large-scale study of the photometric and structural
relations followed by early-type galaxies (ETGs) in the Antlia cluster. Antlia
is the third nearest populous galaxy cluster after Fornax and Virgo (d $\sim
35$ Mpc). A photographic catalog of its galaxy content was built by Ferguson &
Sandage in 1990 (FS90). Afterwards, we performed further analysis of the ETG
population located at the cluster centre. Now, we extend our study covering an
area four times larger, calculating new total magnitudes and colours, instead
of isophotal photometry, as well as structural parameters obtained through
S\'ersic model fits extrapolated to infinity. Our present work involves a total
of 177 ETGs, out of them 56 per cent have been cataloged by FS90 while the rest
(77 galaxies) are newly discovered ones. Medium-resolution GEMINI and VLT
spectra are used to confirm membership when available. Including radial
velocities from the literature, 59 ETGs are confirmed as Antlia members. Antlia
scaling relations mainly support the existence of unique functions (linear and
curved) that join bright and dwarf ETGs, excluding compact ellipticals (cEs).
Lenticular galaxies are outliers only with respect to the curved relation
derived for effective surface brightness versus absolute magnitude. The small
number of bright ellipticals and cEs present in Antlia, prevents us from
testing if the same data can be fitted with two different linear sequences, for
bright and dwarf ETGs. However, adding data from other clusters and groups, the
existence of such sequences is also noticeable in the same scaling relations.
