Two-Dimensional Photographic and CCD Photometry of the SO Galaxy NGC 3115

Photographic and CCD images in B light are used to map the edge-on S0 galaxy NGC 3115, and photometric and geometric standard parameters are derived, including a value for the total magnitude of 9.75. The galaxy image is decomposed into a spheroid and a disk, with the spheroid being modeled using the minor-axis light profile and assuming purely elliptical isophotes. The disk image shows some structure similar to that of a spiral arm system and a certain degree of asymmetry suggesting an inclinaton of 86 deg. Unlike spirals, the cross sections perpendicular to the disk have parabolic light profiles with an apparent scale height increasing with distance from the galaxy center. A ratio of the disk luminosity to the total luminosity of the galaxy of only 0.06 is found.