Statistical approaches in search for astrophysical neutrino sources with Baikal deep underwater telescopes

TL;DR

This paper applies likelihood methods to search for astrophysical neutrino sources using Baikal deep underwater telescopes, setting upper limits on neutrino fluxes and analyzing data from NT200 and NT1000 over multiple celestial scans.

Contribution

It introduces a likelihood-based approach for neutrino source detection with Baikal telescopes and provides new flux upper limits based on extensive data analysis.

Findings

No significant neutrino source detected (less than 1 sigma significance)

Established upper limits on neutrino fluxes at 90% confidence level

Analyzed data from NT200 over 1038 live days and projections for NT1000

Abstract

We use likelihood approach for search for local astrophysical neutrino sources in unbinned versus binned methods with Baikal deep underwater telescopes. We analyze neutrino data sample selected with NT200 telescope for 1038 live days by scanning a celestial map with different nets and for listed gamma ray sources. Significance of most probable location of enhance in measured number of events is found to be less than one sigma. We obtain the upper limits and a sensitivity at 90\% C.L. on neutrino fluxes from listed sources for NT200 and NT1000 correspondingly.