Effects of the sources of reionization on 21-cm redshift-space distortions
2016 (English)In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 456, no 2, 2080-2094 p.Article in journal (Refereed) PublishedText
Stockholm Univ, AlbaNova, Dept Astron, SE-10691 Stockholm, Sweden.;Stockholm Univ, AlbaNova, Oskar Klein Ctr, SE-10691 Stockholm, Sweden.;Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Dept Phys, Prince Consort Rd, London SW7 2AZ, England..
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy. Stockholm Univ, AlbaNova, Dept Astron, SE-10691 Stockholm, Sweden.;Stockholm Univ, AlbaNova, Oskar Klein Ctr, SE-10691 Stockholm, Sweden..
Stockholm Univ, AlbaNova, Dept Astron, SE-10691 Stockholm, Sweden.;Stockholm Univ, AlbaNova, Oskar Klein Ctr, SE-10691 Stockholm, Sweden..
UCL, Dept Phys & Astron, Gower St, London WC1E 6BT, England..
The observed 21 cm signal from the epoch of reionization will be distorted along the line of sight by the peculiar velocities of matter particles. These redshift-space distortions will affect the contrast in the signal and will also make it anisotropic. This anisotropy contains information about the cross-correlation between the matter density field and the neutral hydrogen field, and could thus potentially be used to extract information about the sources of reionization. In this paper, we study a collection of simulated reionization scenarios assuming different models for the sources of reionization. We show that the 21 cm anisotropy is best measured by the quadrupole moment of the power spectrum. We find that, unless the properties of the reionization sources are extreme in some way, the quadrupole moment evolves very predictably as a function of global neutral fraction. This predictability implies that redshift-space distortions are not a very sensitive tool for distinguishing between reionization sources. However, the quadrupole moment can be used as a model-independent probe for constraining the reionization history. We show that such measurements can be done to some extent by first-generation instruments such as LOFAR, while the SKA should be able to measure the reionization history using the quadrupole moment of the power spectrum to great accuracy.
Place, publisher, year, edition, pages
2016. Vol. 456, no 2, 2080-2094 p.
methods: numerical, dark ages, reionization, first stars
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:uu:diva-294590DOI: 10.1093/mnras/stv2812ISI: 000372264200068OAI: oai:DiVA.org:uu-294590DiVA: diva2:930982
FunderSwedish Research Council, 2012-4144