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arXiv · 1909.11681

The low density and magnetization of a massive galaxy halo exposed by a fast radio burst

J. Xavier Prochaska·Jean-Pierre Macquart·Matthew McQuinn·Sunil Simha·Ryan M. Shannon·Cherie K. Day·Lachlan Marnoch·Stuart Ryder·Adam Deller·Keith W. Bannister·Shivani Bhandari·Rongmon Bordoloi·John Bunton·Hyerin Cho·Chris Flynn·Elizabeth K. Mahony·Chris Phillips·Hao Qiu·Nicolas Tejos
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Abstract

Present-day galaxies are surrounded by cool and enriched halo gas extending to hundreds of kiloparsecs. This halo gas is thought to be the dominant reservoir of material available to fuel future star formation, but direct constraints on its mass and physical properties have been difficult to obtain. We report the detection of a fast radio burst (FRB 181112) with arcsecond precision, which passes through the halo of a foreground galaxy. Analysis of the burst shows the halo gas has low net magnetization and turbulence. Our results imply predominantly diffuse gas in massive galactic halos, even those hosting active supermassive black holes, contrary to some previous results.

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J. Xavier Prochaska, Jean-Pierre Macquart, Matthew McQuinn, Sunil Simha, Ryan M. Shannon, Cherie K. Day, Lachlan Marnoch, Stuart Ryder, Adam Deller, Keith W. Bannister, Shivani Bhandari, Rongmon Bordoloi, John Bunton, Hyerin Cho, Chris Flynn, Elizabeth K. Mahony, Chris Phillips, Hao Qiu, Nicolas Tejos. 2019-09-25. The low density and magnetization of a massive galaxy halo exposed by a fast radio burst. https://doi.org/10.1126/science.aay0073

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