CO Tully-Fisher Relation of Star-forming Galaxies at z=0.05-0.3
  The Tully-Fisher relation (TFR) is an empirical relation between galaxy
luminosity and rotation velocity. We present here the first TFR of galaxies
beyond the local Universe that uses carbon monoxide (CO) as the kinematic
tracer. Our final sample includes 25 isolated, non-interacting star-forming
galaxies with double-horned or boxy CO integrated line profiles located at
redshifts z <= 0.3, drawn from a larger ensemble of 67 detected objects. The
best reverse Ks-band, stellar mass and baryonic mass CO TFRs are respectively
M_Ks = (-8.4+/-2.9) [log(W_50/sini)-2.5]+(-23.5 +/- 0.5), log (Mstar/Msun)
=(5.2+/-3.0) [log(W_50/sini)-2.5]+(10.1+/-0.5) and log (Mb/Msun) = (4.9+/-2.8)
[log(W_50/sini)-2.5]+(10.2+/-0.5), where M_Ks is the total absolute Ks-band
magnitude of the objects, Mstar and Mb their total stellar and baryonic masses,
and W_50 the width of their line profile at 50% of the maximum. Dividing the
sample into different redshift bins and comparing to the TFRs of a sample of
local (z = 0) star-forming galaxies from the literature, we find no significant
evolution in the slopes and zero-points of the TFRs since z = 0.3, this in
either luminosity or mass. In agreement with a growing number of CO TFR studies
of nearby galaxies, we more generally find that CO is a suitable and attractive
alternative to neutral hydrogen (HI). Our work thus provides an important
benchmark for future higher redshift CO TFR studies.
