http://arxiv.org/abs/1712.03957
We present Large Binocular Telescope difference imaging data for the final years of four Type II supernovae progenitors. For all four, we find no significant evidence for stochastic or steady variability in the U, B, V, or R-bands. Our limits constrain variability to no more than roughly 5-10% of the expected R-band luminosities of the progenitors. These limits are comparable to the observed variability of red supergiants in the Magellanic Clouds. Based on these four events, the probability of a Type II progenitor having an extended outburst after Oxygen ignition is <37% at 90% confidence.
S. Johnson, C. Kochanek and S. Adams
Wed, 13 Dec 17
50/84
Comments: 9 pages, 8 figures, 1 table. Submitted to MNRAS, comments appreciated