The multiwavelength Tully-Fisher relation with spatially resolved HI kinematics

Abstract

In this paper, we investigate the statistical properties of the Tully-Fisher relation (TFr) for a sample of 32 galaxies with measured distances from the Cepheid period-luminosity relation and/or TRGB stars. We take advantage of panchromatic photometry in 12 bands (from FUV to 4.5 mu m) and of spatially resolved HI kinematics. We use these data together with three kinematic measures (W-50(i), V-max and V-flat) extracted from the global HI profiles or HI rotation curves, so as to construct 36 correlations allowing us to select the one with the least scatter. We introduce a tightness parameter sigma (perpendicular to). of the TFr, in order to obtain a slope-independent measure of the goodness of fit. We find that the tightest correlation occurs when we select the 3.6 mu m photometric band together with the V-flat parameter extracted from the HI rotation curve. Show more