Calibration of the Tully-Fisher relation in the WISE W1 ($3.4\mu \rm m$) and W2 ($4.6\mu \rm m$) Bands

TL;DR

This study calibrates the Tully-Fisher relation in mid-infrared W1 and W2 bands using large galaxy samples, correcting for biases and comparing methods to optimize scatter, and relates findings to previous near-infrared and optical calibrations.

Contribution

Introduces a new iterative bivariate fitting calibration of the Tully-Fisher relation in WISE mid-infrared bands, assessing the impact of different magnitude and velocity measures on scatter.

Findings

Total magnitude and HI linewidths yield smallest scatter.

Calibrations in W1 and W2 bands are consistent with previous near-infrared and optical relations.

Using total magnitudes and HI linewidths provides the most reliable Tully-Fisher calibration.

Abstract

In this paper, we present our calibrations of the TF relation in the mid-infrared W1 ($3.4\mu$m) and W2 ($4.6\mu$m) bands, using large samples 848 galaxies and 857 galaxies in the W1 and W2 bands respectively. In this calibration we performed a correction for the cluster population incompleteness bias, and a morphological type correction. The calibration was performed using a new, iterative bivariate fitting procedure. For these calibrations we used the total absolute magnitudes, and HI linewidths $W_{F50}$ derived from the HI global profiles as a measure of the rotational velocities. We then performed two additional calibrations on the same sample using (i) the isophotal magnitudes and (ii) the average rotational velocities measured along the flat sections of the spatially resolved rotation curves of the galaxies, which were obtained from the empirical conversion between rotational velocity definitions. We compared these three calibrations to determine whether the use of isophotal magnitudes, or spatially resolved rotational velocities have a significant impact on the scatter around the TF relations in the W1 and W2 bands. We found that the original calibrations using total magnitudes and \hi linewidths had the smallest total scatters. These calibrations are given by $M_{\rm Tot, W1} = (2.02 \pm 0.44) - (10.08 \pm 0.17)\log_{10}(W_{F50})$ and $M_{\rm Tot, W2} = (2.00 \pm 0.44) - (10.11 \pm 0.17)\log_{10}(W_{F50})$, with associated total scatters of $\sigma_{W1} = 0.68$ and $\sigma_{W2} = 0.69$. Finally, we compared our calibrations in the mid-infrared bands with previous calibrations in the near-infrared J, H and K bands and the long-wavelength optical I band, which used the same two corrections. The differences between these relations can be explained by considering the different regions and components of spiral galaxies that are traced by the different wavelengths.