The multiwavelength Tully-Fisher relation with spatially resolved H I kinematics

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 μm) and of spatially resolved H I kinematics. We use these data together with three kinematic measures (WI_{50}, Vmax and Vflat) extracted from the global H I profiles or H I rotation curves, so as to construct 36 correlations allowing us to select the one with the least scatter. We introduce a tightness parameter σ⊥ 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 μm photometric band together with the Vflat parameter extracted from the H I rotation curve