| We studied the relations between isophotal shape and other galactic photometric properties for 114 early-type galaxies selected from SDSS DR6 that were also observed with HST. There is no significant correlation between the isophotal shape and the central photometric properties (within 1 Kpc) of early-type galaxies. About one third of "core" galaxies have disky isophotes, while one fourth of "power-law" galaxies are with boxy isophotal shape.We also performd the isophotal analysis for 30 ULIRGs with single nucleus. The results show that at least one third of ULIRGs in last wet merging state have isophotal shape of boxy or irregular. It implys that the merging between gas-rich disk galaxies ("wet-mergers") leads to form elliptical galaxies with both boxy and disky isophotes.Our statistical results show that there are weak correlations between the isophotal shape with galaxy luminosity, velocity dispersion and central photometric properties of early-type galaxies. It indicates that the isophotal shape is not directly related to the early-type galaxies formation by "wet-mergers" or "dry-mergers" . Therefore, the isophotal shape, especially the a4/a, is not a good indicator to describe the dynamical properties of early-type galaxies. |
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