Galaxy formation in the Planck Millennium: the atomic hydrogen content of dark matter haloes

Baugh, CM; Gonzalez-Perez, Violeta; Lagos, Claudia DP; Lacey, Cedric G; Helly, John C; Jenkins, Adrian; Frenk, Carlos S; Benson, Andrew J; Bower, Richard G; Cole, Shaun

Abstract

We present recalibrations of the GALFORM semi-analytical model of galaxy formation in a new N-body simulation with the Planck cosmology. The Planck Millennium simulation uses more than 128 billion particles to resolve the matter distribution in a cube of 800 Mpc on a side, which contains more than 77 million dark matter haloes with mass greater than 2.12 × 109 h−1 M⊙ at this day. Only minor changes to a very small number of model parameters are required in the recalibration. We present predictions for the atomic hydrogen content (H I) of dark matter haloes, which is a key input into the calculation of the H I intensity mapping signal expected from the large-scale structure of the Universe. We find that the H I mass–halo mass relation displays a clear break at the halo mass above which AGN heating suppresses gas cooling, ≈3 × 1011h−1 M⊙. Below this halo mass, the H I content of haloes is dominated by the central galaxy; above this mass it is the combined H I content of satellites that prevails. We find that the H I mass–halo mass relation changes little with redshift up to z = 3. The bias of H I sources shows a scale dependence that gets more pronounced with increasing redshift.

Citation

Baugh, C., Gonzalez-Perez, V., Lagos, C. D., Lacey, C. G., Helly, J. C., Jenkins, A., …Cole, S. (2019). Galaxy formation in the Planck Millennium: the atomic hydrogen content of dark matter haloes. Monthly Notices of the Royal Astronomical Society, 483(4), 4922-4937. https://doi.org/10.1093/mnras/sty3427

• Journal Article Type: Article
• Acceptance Date: Dec 14, 2018
• Online Publication Date: Dec 18, 2018
• Publication Date: Mar 11, 2019
• Deposit Date: Jan 22, 2019
• Publicly Available Date: Jan 23, 2019
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 483
• Issue: 4
• Pages: 4922-4937
• DOI: https://doi.org/10.1093/mnras/sty3427
• Public URL: https://durham-repository.worktribe.com/output/1339204