Surface photometry of LSB edge-on galaxies

Abstract

We present results of surface photometry for eleven edge-on galaxies observed with the 6-m telescope at the Special Astrophysical Observatory of the Russian Academy of Sciences. The photometric scale length, the scale height, and the central surface brightness of the stellar disks for the galaxies were found using photometric cuts made parallel to the major and the minor axes for each galaxy. We show that four galaxies in our sample that were visually classified as objects of lowest surface brightness in the Revised Flat Galaxies Catalog have LSB (low surface brightness) disks. Stellar disks of our LSB galaxies are thinner than HSB (high surface brightness) ones. There is a good correlation between the central surface brightness of the stellar disk and its ratio of vertical to radial scales. The ratio of the disk photometric scales enables us to estimate the mass of the spherical galactic subsystem using results from numerical modeling. Combining our results with published rotation curves we determined the mass of dark halos for the galaxies in our sample. The LSB galaxies tend to harbor relatively more massive spherical subsystems than those of HSB's. Indeed, we found no systematic difference between our LSB and HSB objects in dark halo masses considering it separately from the bulge. At the same time, the inferred mass/luminosity ratio for the LSB disks appears to be systematically higher, when compared to the ratio for HSB ones.