Combined significance of spatial coincidence of high energy neutrinos from PSR B1509-58 by Super-Kamiokande and MACRO

TL;DR

This paper analyzes the combined significance of neutrino detections from PSR B1509-58 by Super-Kamiokande and MACRO, estimating a 0.4% chance coincidence probability and proposing tests to confirm an astrophysical origin.

Contribution

It presents a combined statistical analysis of neutrino excess from PSR B1509-58 and suggests methods to verify its astrophysical nature, enhancing source detection reliability.

Findings

Observed angular excess with 2.6σ significance

Chance coincidence probability estimated at 0.4%

Proposed tests for astrophysical signal confirmation

Abstract

In their searches for astrophysical point sources of high energy neutrinos, both the Super-Kamiokande and MACRO neutrino detectors saw the largest angular excess from the same source, viz. PSR B1509-58. We estimate the probability for the observed number of events by {\it both} Super-Kamiokande and MACRO to be a chance coincidence due to atmospheric neutrino background. We find that this probability is about 0.4%, corresponding to 2.6$\sigma$ significance. We also propose some additional tests to ascertain if this excess corresponds to an astrophysical signal or is only a background event.