All-sky search for time-integrated neutrino emission from astrophysical sources with 7 years of IceCube data

TL;DR

This paper reports a comprehensive seven-year search for astrophysical neutrino point sources using IceCube data, achieving improved sensitivity but finding no significant source clustering.

Contribution

It presents the longest IceCube neutrino point-source search to date, with enhanced sensitivity and no detection of significant sources, refining constraints on neutrino emission from astrophysical objects.

Findings

No significant neutrino source detected

Sensitivity improved by 38% over previous four-year analysis

Constraints placed on neutrino flux from candidate sources

Abstract

Since the recent detection of an astrophysical flux of high energy neutrinos, the question of its origin has not yet fully been answered. Much of what is known about this flux comes from a small event sample of high neutrino purity, good energy resolution, but large angular uncertainties. In searches for point-like sources, on the other hand, the best performance is given by using large statistics and good angular reconstructions. Track-like muon events produced in neutrino interactions satisfy these requirements. We present here the results of searches for point-like sources with neutrinos using data acquired by the IceCube detector over seven years from 2008--2015. The discovery potential of the analysis in the northern sky is now significantly below $E_\nu^2d\phi/dE_\nu=10^{-12}\:\mathrm{TeV\,cm^{-2}\,s^{-1}}$, on average $38\%$ lower than the sensitivity of the previously published analysis of four years exposure. No significant clustering of neutrinos above background expectation was observed, and implications for prominent neutrino source candidates are discussed.