Skip to main content

Research Repository

See what's under the surface

Advanced Search

Diagnosing galactic feedback with line broadening in the low redshift Lyα forest

Viel, Matteo; Haehnelt, Martin G.; Bolton, James S.; Kim, Tae-Sun; Puchwein, Ewald; Nasir, Fahad; Wakker, Bart P.

Authors

Matteo Viel

Martin G. Haehnelt

James S. Bolton

Tae-Sun Kim

Ewald Puchwein

Fahad Nasir

Bart P. Wakker



Abstract

We compare the low-redshift (z 0.1) Lyα forest from hydrodynamical simulations with data from the Cosmic Origins Spectrograph. We find the tension between the observed number of lines with b-parameters in the range of 25–45 km s−1 and the predictions from simulations that incorporate either vigorous feedback from active galactic nuclei or that exclude feedback altogether. The gas in these simulations is, respectively, either too hot to contribute to the Lyα absorption or too cold to produce the required linewidths. Matching the observed b parameter distribution therefore requires feedback processes that thermally or turbulently broaden the absorption features without collisionally (over)ionizing hydrogen. This suggests that the Lyα forest b-parameter distribution is a valuable diagnostic of galactic feedback in the low-redshift Universe. We furthermore confirm that the low-redshift Lyα forest column density distribution is better reproduced by an ultraviolet background with the H I photoionization rate a factor of 1.5–3 higher than predicted by Haardt and Madau.

Journal Article Type Article
Publication Date Jan 11, 2017
Journal Monthly Notices of the Royal Astronomical Society: Letters
Electronic ISSN 1745-3933
Publisher Oxford University Press
Peer Reviewed Peer Reviewed
Volume 467
Issue 1
Article Number L86-L90
APA6 Citation Viel, M., Haehnelt, M. G., Bolton, J. S., Kim, T., Puchwein, E., Nasir, F., & Wakker, B. P. (2017). Diagnosing galactic feedback with line broadening in the low redshift Lyα forest. Monthly Notices of the Royal Astronomical Society: Letters, 467(1), https://doi.org/10.1093/mnrasl/slx004
DOI https://doi.org/10.1093/mnrasl/slx004
Keywords methods: numerical, intergalactic medium, quasars: absorption lines, diffuse radiation, large-scale structure of Universe
Publisher URL https://academic.oup.com/mnrasl/article-lookup/doi/10.1093/mnrasl/slx004
Copyright Statement Copyright information regarding this work can be found at the following address: http://eprints.nottingh.../end_user_agreement.pdf
Additional Information This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society © 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.

Files

slx004.pdf (296 Kb)
PDF

Copyright Statement
Copyright information regarding this work can be found at the following address: http://eprints.nottingham.ac.uk/end_user_agreement.pdf





You might also like



Downloadable Citations

;