Poster Presentation Astronomical Society of Australia Annual Scientific Meeting including HWWS 2013

HI stacking can be used to measure edge-on rotation velocities for use in the Tully-Fisher relation (#249)

Scott A Meyer 1 , Martin Meyer 1 , Danail Obreschkow 1
  1. Physics, ICRAR, Crawley, Western Australia, Australia

The Tully-Fisher relation1  is an empirical relation between the baryonic and dark matter components of spiral galaxies. In order to reduce or completely exclude the largest source of error in constructing the Tully-Fisher relation, inclination errors, we have investigated stacked HI profile widths, which do not require inclination information. We find a correlation between the width of a stacked HI profile and the maximum rotational velocity of the galaxies used in the stack.  We propose that this correlation could be used to construct a Tully-Fisher relation from a set of stacked profiles that mimics the Tully-Fisher relation produced by the input galaxies. We have investigated analytical galaxies, simulated galaxies and the HIPASS data set.  We find1  that HI stacked profiles can be used in place of individual profiles for use in the Tully-Fisher relation.

  1. Tully, R., & Fisher, J. (1977). A new method of determining distances to galaxies. Astronomy & Astrophysics, 54(3), 661.