Open access
Datum
2019-05Typ
- Journal Article
Abstract
We use the results of previous work building a halo model formalism for the distribution of neutral hydrogen, along with experimental parameters of future radio facilities, to place forecasts on astrophysical and cosmological parameters from next-generation surveys. We consider 21 cm intensity mapping surveys conducted using the BINGO, CHIME, FAST, TianLai, MeerKAT, and SKA experimental configurations. We work with the five-parameter cosmological data set of {Ωₘ, σ₈, h, nₛ, Ωb} assuming a flat ΛCDM model, and the astrophysical parameters {vc,₀, β} which represent the cut-off and slope of the H I–halo mass (H IHM) relation. We explore (i) quantifying the effects of the astrophysics on the recovery of the cosmological parameters, (ii) the dependence of the cosmological forecasts on the details of the astrophysical parametrization, and (iii) the improvement of the constraints on probing smaller scales in the H I power spectrum. For an SKA I MID intensity mapping survey alone, probing scales up to ℓₘₐₓ = 1000, we find a factor of 1.1–1.3 broadening in the constraints on Ωb and Ωm, and of 2.4–2.6 on h, nₛ and σ₈, if we marginalize over astrophysical parameters without any priors. However, even the prior information coming from the present knowledge of the astrophysics largely alleviates this broadening. These findings do not change significantly on considering an extended H IHM relation, illustrating the robustness of the results to the choice of the astrophysical parametrization. Probing scales up to ℓₘₐₓ = 2000 improves the constraints by factors of 1.5–1.8. The forecasts improve on increasing the number of tomographic redshift bins, saturating, in many cases, with 4–5 redshift bins. We also forecast constraints for intensity mapping with other experiments, and draw similar conclusions. Mehr anzeigen
Persistenter Link
https://doi.org/10.3929/ethz-b-000348862Publikationsstatus
publishedExterne Links
Zeitschrift / Serie
Monthly Notices of the Royal Astronomical SocietyBand
Seiten / Artikelnummer
Verlag
Oxford University PressThema
cosmology: observations; cosmology: theory; radio lines: galaxiesOrganisationseinheit
03928 - Refregier, Alexandre / Refregier, Alexandre
Anmerkungen
It was possible to publish this article open access thanks to a Swiss National Licence with the publisher.