A Survey of Novae in M83

The results of the first synoptic survey of novae in the barred spiral and starburst galaxy, M83 (NGC 5236), are presented. A total of 19 novae and one background supernova were discovered during the course of a nearly seven-year survey comprised of over 200 individual nights of observation between 2012 December 12 and 2019 March 14. After correcting for the limiting magnitude and the spatial and temporal coverage of the survey, the nova rate in M83 was found to be $R=19^{+5}_{-3}$ yr$^{-1}$. This rate, when normalized to the $K$-band luminosity of the galaxy, yields a luminosity-specific nova rate, $\nu_K = 3.0^{+0.9}_{-0.6}\times10^{-10}$ yr$^{-1} L_{\odot,K}^{-1}$. The spatial distribution of the novae is found to be more extended than the overall galaxy light suggesting that the observed novae are likely dominated by a disk population. This result is consistent with the observed nova light curves which reveal that the M83 novae are on average more luminous at maximum light and fade faster when compared with novae observed in M31. Generally, the more luminous M83 novae were observed to fade more rapidly, with the complete sample being broadly consistent with a linear Maximum-Magnitude vs Rate of Decline relation.