The Second Radio Synchrotron Background Workshop: Conference Summary and Report

TL;DR

This paper summarizes discussions from the second radio synchrotron background workshop, focusing on the unexplained excess radio emission and outlining future research priorities to understand its origins.

Contribution

It provides a comprehensive overview of current challenges and proposes specific next steps for investigating the diffuse radio background.

Findings

Radio background exceeds known sources by several times

Identified key observational strategies for future research

Supported development of calibrated sky maps

Abstract

We summarize the second radio synchrotron background workshop, which took place June 15-17, 2022 in Barolo, Italy. This meeting was convened because available measurements of the diffuse radio zero level continue to suggest that it is several times higher than can be attributed to known Galactic and extragalactic sources and processes, rendering it the least well understood electromagnetic background at present and a major outstanding question in astrophysics. The workshop agreed on the next priorities for investigations of this phenomenon, which include searching for evidence of the Radio Sunyaev-Zel'dovich effect, carrying out cross-correlation analyses of radio emission with other tracers, and supporting the completion of the 310 MHz absolutely calibrated sky map project.