# Correlation of IceCube neutrinos with the 2MASS Redshift Survey

## TL;DR

This study investigates whether high-energy neutrinos detected by IceCube are spatially correlated with galaxy distributions from the 2MASS Redshift Survey, aiming to identify their astrophysical sources.

## Contribution

It introduces a novel analysis correlating IceCube neutrino directions with local galaxy density, providing constraints on neutrino flux from the nearby universe.

## Key findings

- No significant correlation found between neutrinos and galaxy density.
- Sets upper limits on neutrino flux from the local universe.
- Provides insights into the origins of high-energy astrophysical neutrinos.

## Abstract

Since the detection of high energy astrophysical neutrinos in IceCube, there has been a search for their sources. Although recent evidence of neutrinos from a flaring blazar could explain some of the neutrino flux, sources for the remainder are still unknown. This analysis searches for neutrinos produced via interactions between diffuse intergalactic Ultra-High Energy Cosmic Rays (UHECR) and matter. In this work the local galaxy density serves as the target for cosmic ray interactions, thus neutrinos produced from these interactions are expected to trace the galaxies spatially. The spatial distribution of galaxies within the local universe (z < 0.10) as seen in the 2MASS Redshift Survey (2MRS) is anisotropic. Here we present an analysis that searches for the spatial correlation between the arrival directions of neutrinos observed at the IceCube neutrino observatory and the directions of high galaxy density in the local universe. No such correlation was found and this analysis presents limits on the flux of neutrinos from the local universe.