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arXiv · 1503.08983

Forecasts for the detection of the magnetised cosmic web from cosmological simulations

F. Vazza·C. Ferrari·M. Brüggen·A. Bonafede·C. Gheller·P. Wang
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Abstract

The cosmic web contains a large fraction of the total gas mass in the universe but is difficult to detect at most wavelengths. Synchrotron emission from shock-accelerated electrons may offer the chance of imaging the cosmic web at radio wavelengths. In this work we use 3D cosmological ENZO-MHD simulations (combined with a post-processing renormalisation of the magnetic field to bracket for missing physical ingredients and resolution effects) to produce models of the radio emission from the cosmic web. In post-processing we study the capabilities of 13 large radio surveys to detect this emission. We find that surveys by LOFAR, SKA1-LOW and MWA have a chance of detecting the cosmic web, provided that the magnetisation level of the tenuous medium in filaments is of the order of 1% of the thermal gas energy.

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F. Vazza, C. Ferrari, M. Brüggen, A. Bonafede, C. Gheller, P. Wang. 2015-03-31. Forecasts for the detection of the magnetised cosmic web from cosmological simulations. https://doi.org/10.1051/0004-6361%2F201526228

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