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 ^ { \prime } < 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 \pm 142 km s ^ { -1 } .
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 .