The host dark matter haloes of [O II] emitters at 0.5 < z < 1.5

Gonzalez-Perez, V.; Comparat, J.; Norberg, P.; Baugh, C.M.; Contreras, S.; Lacey, C.; McCullagh, N.; Orsi, A.; Helly, J.; Humphries, J.

Abstract

Emission line galaxies (ELGs) are used in several ongoing and upcoming surveys (SDSSIV/eBOSS, DESI) as tracers of the dark matter distribution. Using a new galaxy formation model, we explore the characteristics of [O II] emitters, which dominate optical ELG selections at z 1. Model [O II] emitters at 0.5 < z < 1.5 are selected to mimic the DEEP2, VVDS, eBOSS and DESI surveys. The luminosity functions of model [O II] emitters are in reasonable agreement with observations. The selected [O II] emitters are hosted by haloes with Mhalo ≥ 1010.3h−1M, with ∼90 per cent of them being central star-forming galaxies. The predicted mean halo occupation distributions of [O II] emitters have a shape typical of that inferred for star-forming galaxies, with the contribution from central galaxies, N[O II] cen, being far from the canonical step function. The N[O II] cen can be described as the sum of an asymmetric Gaussian for discs and a step function for spheroids, which plateau below unity. The model [O II] emitters have a clustering bias close to unity, which is below the expectations for eBOSS and DESI ELGs. At z ∼ 1, a comparison with observed g-band-selected galaxy, which is expected to be dominated by [O II] emitters, indicates that our model produces too few [O II] emitters that are satellite galaxies. This suggests the need to revise our modelling of hot gas stripping in satellite galaxies.

Citation

Gonzalez-Perez, V., Comparat, J., Norberg, P., Baugh, C., Contreras, S., Lacey, C., …Humphries, J. (2018). The host dark matter haloes of [O II] emitters at 0.5 < z < 1.5. Monthly Notices of the Royal Astronomical Society, 474(3), 4024-4038. https://doi.org/10.1093/mnras/stx2807

• Journal Article Type: Article
• Acceptance Date: Oct 26, 2017
• Online Publication Date: Oct 30, 2017
• Publication Date: Mar 1, 2018
• Deposit Date: Jan 15, 2018
• Publicly Available Date: Jan 16, 2018
• 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: 474
• Issue: 3
• Pages: 4024-4038
• DOI: https://doi.org/10.1093/mnras/stx2807
• Public URL: https://durham-repository.worktribe.com/output/1341586