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arXiv · 1910.04310

The Relationship Between Galaxy ISM and Circumgalactic Gas Metallicities

Glenn G. Kacprzak·Stephanie K. Pointon·Nikole M. Nielsen·Christopher W. Churchill·Sowgat Muzahid·Jane C. Charlton
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Abstract

We present ISM and CGM metallicities for 25 absorption systems associated with isolated star-forming galaxies ( =0.28) with 9.4 17.2) reside along the minor axis. This suggest N(HI) could be a useful indicator of accretion/outflows. We conclude that CGM is not well mixed, given the range of galaxy-CGM metallicities, and that metallicity at low redshift might not be a good tracer of CGM processes. Furthermore we should replace integrated line-of-sight, single phase, metallicities with multi-phase, cloud-cloud metallicities, which could be more indicative of the physical processes within the CGM.

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Glenn G. Kacprzak, Stephanie K. Pointon, Nikole M. Nielsen, Christopher W. Churchill, Sowgat Muzahid, Jane C. Charlton. 2019-10-10. The Relationship Between Galaxy ISM and Circumgalactic Gas Metallicities. https://doi.org/10.3847/1538-4357%2Fab4c3c

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