Detecting the cosmic web with radio surveys

TL;DR

This paper explores the potential of upcoming low-frequency radio surveys to detect the cosmic web's faint emission, which can reveal insights into cosmic magnetization and structure formation.

Contribution

It assesses the feasibility of detecting the cosmic web with current simulations and discusses how radio observations can distinguish different magnetization origins.

Findings

Upcoming radio surveys can potentially detect the cosmic web.

Radio detections can constrain gas magnetization levels.

Statistical analysis can differentiate magnetogenesis scenarios.

Abstract

We study the challenges to detect the cosmic web at radio wavelengths with state-of-the-art cosmological simulations of extragalactic magnetic fields. The incoming generation of radio surveys operating at low frequency, like LOFAR, SKA-LOW and MWA will have the best chance to detect the large-scale, low surface brightness emission from the shocked cosmic web. The detected radio emission will enable to constrain the average magnetisation level of the gas in filaments and the acceleration efficiency of electrons by strong shocks. In case of detections, through statistical modelling (e.g. correlation functions) it will be possible to discriminate among competing scenarios for the magnetisation of large-scale structures (i.e. astrophysical versus primordial scenarios), making radio surveys an important probe of cosmic magnetogenesis.