2MTF I. The Tully-Fisher Relation in the 2MASS J, H and K Bands

TL;DR

This paper establishes a universal Tully-Fisher relation in the 2MASS J, H, and K bands, revealing a steeper slope at longer wavelengths and dependence on galaxy morphology, with implications for distance measurements.

Contribution

It provides the first bias-corrected, universal Tully-Fisher template in the 2MASS bands, including slope, zeropoint, and scatter analysis across galaxy types.

Findings

Steeper TF slope at longer wavelengths, close to L ∝ v^4 in K-band.

TF relation is steeper for later type spirals.

Intrinsic scatter does not significantly vary with wavelength.

Abstract

The 2 Micron All-Sky Survey (2MASS) Tully-Fisher Survey (2MTF) aims to measure Tully-Fisher (TF) distances to all bright inclined spirals in the 2MASS Redshift Survey (2MRS). Essential to this project is a universal calibration of the TF relation in the 2MASS J (1.2 um), H (1.6 um) and K (2.2 um) bands. We present the first bias corrected or universal TF template in these bands. We find that the slope of the TF relation becomes steeper as the wavelength increases being close to L \propto v^4 in K-band and L \propto v^3.6 in J and H-bands. We also investigate the dependence on galaxy morphology showing that in all three bands the relation is steeper for later type spirals which also have a dimmer TF zeropoint than earlier type spirals. We correct the final relation to that for Sc galaxies. Finally we study the scatter from the TF relation fitting for a width dependent intrinsic scatter which is not found to vary significantly with wavelength.