  This paper presents a multicolor study of the nearby cluster of galaxies
Abell 168 (z=0.045) with 13 intermediate-band filters in the
Beijing-Arizona-Taiwan-Connecticut (BATC) filter system. After a
cross-identification between the photometric data obtained from the BATC and
the Sloan Digital Sky Survey (SDSS), a catalog containing 1553 galaxies down to
r'<20.0 mag is achieved, which includes 121 spectroscopically confirmed member
galaxies. The technique of photometric redshift has been applied to all these
galaxies with combined 18-band (13 from BATC and 5 from SDSS) spectral energy
distributions (SEDs), in order to perform a faint membership selection in Abell
168. As a result, 255 galaxies are newly selected as the member candidates.
  Based on the enlarged sample of cluster galaxies, the spatial distribution
and dynamics of Abell 168 are investigated. In the light of the spatial
distribution of the member galaxies and the 0.2-3.5 keV X-ray image by Einstein
observatory, it seems that Abell 168 consists of two merging subclusters with a
relative radial velocity of 264 +/- 142 km/s. With the help of ROSTAT software,
a detailed investigation of the dynamics shows the intrinsic difference in the
velocity distributions for these two subclusters. Under a linear two-body
model, they are found to be a gravitationally bound system with 92%
probability. The slight deviation of the local velocity distribution from the
overall distribution in the central region may suggest a picture of head-on
collision in the projection plane. By using a double Schechter function, the
close examination of the luminosity functions reveals the different galaxy
content of these two subclusters, which implies the merging process is possibly
at the early stage.
