An Estimate of the Distance to M100 in the Virgo Cluster via VLBI of SN1979C: Updates and Prospects

Abstract

A VLBI determination, at time t after the explosion, of the angular radius, Θ, of a supernova’s radiosphere, coupled with an optical-spectroscopic determination of the radial expansion velocity ν _shock, at time t0 after the explosion, of the supernova’s shockfront allows estimates to be made of the distance, D., to the supernova’s host galaxy and of Hubble’s constant (BARTEL [1]; BARTEL et al. [2]; see also BARTEL [3], for a comparison of this method with other methods (e.g., BRANCH [4]) that use supernovae as distance indicators):

$$D = \frac{{vshockt\mu \eta }}{{\Theta m\kappa }}{{\left[ {\frac{t}{{{{t}_{0}}}}} \right]}^{{m - 1}}} $$

(1)

$${{H}_{0}} = \frac{{\nu redshift + \nu \inf all}}{D} $$

(2)