The 2MASS Tully-Fisher relation for flat edge-on galaxies

Abstract

The spiral edge-on galaxies from the "Revised Flat Galaxy Catalog" (RFGC) are identified with the Extended Source Catalog of the Two Micron All Sky Survey (2MASS). The relative number of 2MASS detected galaxies is 2996/4236 = 0.71. We consider the statistical properties of the Tully-Fisher relations for the edge-on galaxies in the B, I, J, H, and Ks bands. The slope of derived TF relations increases steadily from 4.9 in the B band to 9.3 in the K one. The effect is mainly due to the internal extinction, which is different in dwarf and giant spiral galaxies seen edge-on, that leads to the tight correlation between galaxy color and luminosity. The moderate scatter of the RFGC galaxies in the "color-luminosity" diagram, 0m.86, provides us with a "cheap" method of mass measurements of distances to galaxies on the basis of modern photometric sky surveys.