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arXiv · 1507.08950

An HI View of Galaxy Conformity: HI-rich Environment around HI-excess Galaxies

Jing Wang·Paolo Serra·Gyula I. G. Jozsa·Baerbel Koribalski·Thijs van der Hulst·Peter Kamphuis·Cheng Li·Jian Fu·Ting Xiao·Roderik Overzier·Mark Wieringa·Enci Wang
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Abstract

Using data taken as part of the Bluedisk project we study the connection between neutral hydrogen (HI) in the environment of spiral galaxies and that in the galaxies themselves. We measure the total HI mass present in the environment in a statistical way by studying the distribution of noise peaks in the HI data cubes obtained for 40 galaxies observed with WSRT. We find that galaxies whose HI mass fraction is high relative to standard scaling relations have an excess HI mass in the surrounding environment as well. Gas in the environment consists of gas clumps which are individually below the detection limit of our HI data. These clumps may be hosted by small satellite galaxies and\or be the high-density peaks of a more diffuse gas distribution in the inter-galactic medium. We interpret this result as an indication for a picture in which the HI-rich central galaxies accrete gas from an extended gas reservoir present in their environment.

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Jing Wang, Paolo Serra, Gyula I. G. Jozsa, Baerbel Koribalski, Thijs van der Hulst, Peter Kamphuis, Cheng Li, Jian Fu, Ting Xiao, Roderik Overzier, Mark Wieringa, Enci Wang. 2015-07-31. An HI View of Galaxy Conformity: HI-rich Environment around HI-excess Galaxies. https://doi.org/10.1093/mnras%2Fstv1767

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