Modelling the number density of Hα emitters for future spectroscopic near-IR space missions

Pozzetti, L.; Hirata, C.M.; Geach, J.E.; Cimatti, A.; Baugh, C.; Cucciati, O.; Merson, A.; Norberg, P.; Shi, D.

Abstract

Context. The future space missions Euclid and WFIRST-AFTA will use the Hα emission line to measure the redshifts of tens of millions of galaxies. The Hα luminosity function at z> 0.7 is one of the major sources of uncertainty in forecasting cosmological constraints from these missions. Aims. We construct unified empirical models of the Hα luminosity function spanning the range of redshifts and line luminosities relevant to the redshift surveys proposed with Euclid and WFIRST-AFTA. Methods. By fitting to observed luminosity functions from Hα surveys, we build three models for its evolution. Different fitting methodologies, functional forms for the luminosity function, subsets of the empirical input data, and treatment of systematic errors are considered to explore the robustness of the results. Results. Functional forms and model parameters are provided for all three models, along with the counts and redshift distributions up to z ~ 2.5 for a range of limiting fluxes (FHα> 0.5 − 3 × 10-16 erg cm-2 s-1) that are relevant for future space missions. For instance, in the redshift range 0.90 1 and 2 × 10-16 erg cm-2 s-1, and 32 000–48 0000 for FHα> 0.5 × 10-16 erg cm-2 s-1 in the extended redshift range 0.40

Citation

Pozzetti, L., Hirata, C., Geach, J., Cimatti, A., Baugh, C., Cucciati, O., …Shi, D. (2016). Modelling the number density of Hα emitters for future spectroscopic near-IR space missions. Astronomy & Astrophysics, 590, https://doi.org/10.1051/0004-6361/201527081

• Journal Article Type: Article
• Acceptance Date: Feb 16, 2016
• Online Publication Date: Apr 28, 2016
• Publication Date: Jun 1, 2016
• Deposit Date: May 24, 2016
• Publicly Available Date: Jun 16, 2016
• Journal: Astronomy and astrophysics.
• Print ISSN: 0004-6361
• Electronic ISSN: 1432-0746
• Publisher: EDP Sciences
• Peer Reviewed: Peer Reviewed
• Volume: 590
• DOI: https://doi.org/10.1051/0004-6361/201527081
• Public URL: https://durham-repository.worktribe.com/output/1380995