Search for the potential electromagnetic counterparts of neutrino events in SDSS galaxies at z<0.1

TL;DR

This study searches for electromagnetic counterparts to high-energy neutrino events by analyzing spatial coincidences with SDSS galaxies at low redshift, aiming to identify potential host galaxies for neutrino sources.

Contribution

It introduces a correlation analysis between SDSS galaxies and neutrino events, identifying promising candidate host galaxies for high-energy neutrino sources.

Findings

Six candidate galaxies identified as potential neutrino source hosts.

Three galaxies associated with IceCube Gold alerts.

Three galaxies associated with neutrino-electromagnetic coincidence events.

Abstract

Identification of electromagnetic emission in coincidence with high-energy neutrinos is fundamentally important for multimessenger astronomy. Such observations are essential for constraining source localization, determining the source type, and understanding emission mechanisms. Typically, they require following up a neutrino alert (IceCube issues two alert streams: Gold, with at least 50 percent probability of astrophysical origin, and Bronze, with at least 30 percent probability) with an electromagnetic facility, primarily in X-ray and gamma-ray bands. Another approach involves electromagnetic monitoring of hot spots in the IceCube skymap, i.e., positions exceeding the instrument sensitivity. An alternative method consists in performing correlation analysis across available neutrino events and source catalogs. We searched for spatial coincidence between galaxies from SDSS and high-energy neutrino events. The analysis includes IceCube Gold alerts and neutrino-electromagnetic coincidence events from AMON (Astrophysical Multimessenger Observatory Network), identified through the end of September 2025. We examined galaxies from the morphological catalog at redshifts 0.02 to 0.1, which contains 315,776 SDSS DR9 objects with absolute stellar magnitudes in the range from -24 to -13 in the r band. Among 59 IceCube Gold alerts, we found three with only one galaxy (SDSS J231231.52+033415.1) within the 50 percent containment radius. Among 24 neutrino-electromagnetic coincidence events, three more contain only one galaxy (SDSS J220711.14+122535.9) within the same radius. These six galaxies represent the most promising candidates for potential host galaxies of neutrino sources. We summarize their available multiwavelength data and the ZTF light curves obtained from 2018 to 2025.