Wide Field CCD Surface Photometry of the Giant Elliptical Galaxy NGC 4472 in the Virgo Cluster

We present deep wide field (16.4× 16.4 ) Washington CT1 CCD surface photometry of the giant elliptical galaxy NGC 4472, the brightest member in the Virgo cluster. Our data cover a wider field than any previous CCD photometry as well as going deeper. Surface brightness profiles of NGC 4472 are not well fit by a single King model, but they can be fit approximately by two King models: with separate models for the inner and outer regions. Surface brightness profiles for the outer region can also be fit approximately by a deVaucouleurs law. There is clearly a negative color gradient within 3 of NGC 4472, in the sense that the color gets bluer with increasing radius. The slope of the color gradient for this region is derived to be ∆μ(C − T1) = –0.08 mag arcsec for ∆ log r = 1, which corresponds to a metallicity gradient of ∆ [Fe/H] = −0.2 dex. However, the surface color gets redder slowly with increasing radius beyond 3. A comparison of the structural parameters of NGC 4472 in C and T1 images has shown that there is little difference in the ellipse shapes between isochromes and isophotes. In addition, photometric and structural parameters of NGC 4472 have been determined.