Could a Reported 2007 Analysis of Super-Kamiokande Data Have Missed a Detectable Supernova Signal from Andromeda?
Figure 1
On a plot of versus the figure shows the search windows used in the original 2007 analysis (solid and dashed rectangles) and the “two-triangle search window” that is based on the assumption of 4.0 eV and 21.4 eV mass eigenstates in SN 1987A. Note that as the two-triangle search window slides along the -axis, it would contain the 3 simulated events for the position shown. The value of the total horizontal width along the time axis of the two-triangle search window is proportional to and it is 182 s for MeV and 62 s for MeV. When MeV, the 20 s wide rectangular search window would be the skinny (fat) rectangle. Hence, we see that both the fat and the skinny rectangles would contain only one event at a time (as it slides along ), and it would miss the hypothetical signal. Moreover, the two-triangle search window with the choice MeV would also miss the signal because in this case the 3 events would not be as depicted in the figure but would be spread out in time threefold from their depiction there, when the time axis is in units of seconds.
