Relationships among detector signals recorded during events SN1987A and GW170817

Abstract

The temporal coincidences of events detected in four neutrino detectors and two gravitational antennas still remains among the most puzzling phenomena associated with SN1987A. The coincidences form a six-hour signal approximately coincident in time with the well-known LSD signal at 2h52m UT on 23/02/1987. After 30 years of research, the characteristics and the shape of the six-hour signal have been studied quite well, but the mechanisms of its formation have not been fully understood as of yet. Here we suggest that data obtained from another technology, radioactive decays, might provide new insights into the origin of signals previously seen in neutrino detectors and gravity wave detectors. On August 17, 2017, at 12h41m UT, the GW170817 signal was detected by LIGO and Virgo. At the same time, an approximately 7-hour long signal coincident with GW170817 was detected in the Si/Cl experiment on precision measurement of the 32 Si half-life. We show that the Si/Cl signal is unexpectedly similar to the six-hour signal from SN1987A. In addition, we establish that the sources of the coinciding events are similar to those of the Si/Cl signal. To explain the surprising similarities in both signals, we present a mechanism which could in principle account for this phenomenon in terms of a local increase in the density of axionic dark matter induced by a gravity wave.

Simulation of the LSD Response to the Neutrino Burst from SN 1987A

“…The closeness of the LSD pulse amplitudes to the detection threshold ∼ 7 MeV may suggest a "background" origin of the signal. The connection of the change in the background of the experiment (the number of radionuclide decays in the soil surrounding the detector and its materials) with the SN 1987A explosion is discussed in [59].…”

“…• the LSD signal enters into the central part of the unique and unexplainable 6-hour event in the interval approximately from 1 to 7 hours UT on February 23, 1987, formed by the set of experimental data from four neutrino detectors and two gravitational wave detectors in Rome and Maryland that operated during the SN1987A explosion [59,61].…”