How accurately can 21cm tomography constrain cosmology

By Y. Mao, Max Tegmark, M. McQuinn, M. Zaldarriaga, Oliver Zahn. 2008

220 citations recorded by the source corpus.

There is growing interest in using 3-dimensional neutral hydrogen mapping with the redshifted 21 cm line as a cosmological probe. However, its utility depends on many assumptions. To aid experimental planning and design, we quantify how the precision with which cosmological parameters can be measured depends on a broad range of assumptions, focusing on the 21 cm signal from $6lzl20$. We cover assumptions related to modeling of the ionization power spectrum, to the experimental specifications like array layout and detector noise, to uncertainties in the reionization history, and to the level of contamination from astrophysical foregrounds. We derive simple analytic estimates for how various assumptions affect an experiment's sensitivity, and we find that the modeling of reionization is the most important, followed by the array layout. We present an accurate yet robust method for measuring cosmological parameters that exploits the fact that the ionization power spectra are rather smooth functions that can be accurately fit by 7 phenomenological parameters. We find that for future experiments, marginalizing over these nuisance parameters may provide constraints almost as tight on the cosmology as if 21 cm tomography measured the matter power spectrum directly. A future square kilometer array optimized for 21 cm tomography could improve the sensitivity to spatial curvature and neutrino masses by up to 2 orders of magnitude, to $\ensuremath{\Delta}{\ensuremath{\Omega}}_{k}\ensuremath{\approx}0.0002$ and $\ensuremath{\Delta}{m}_{\ensuremath{\nu}}\ensuremath{\approx}0.007\text{ }\text{ }\mathrm{eV}$, and give a $4\ensuremath{\sigma}$ detection of the spectral index running predicted by the simplest inflation models.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/d098cfd7f4ff240432bb14c74e94edcffd0b4839

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Citations in the corpus

Evolution of the Intergalactic Opacity: Implications for the Ionizing Background, Cosmic Star Formation, and Quasar Activity (2008, background): “…probes of the epoch of reionization, such as redshifted 21-cm emission and high-redshift Lyα emitters (e.g., Zaldarriaga et al. 2004; McQuinn et al. 2007a; Mao et al. 2008), whose detailed interpretation will rely on our understanding of the morphology of a reionization and its origin.”
Reionization and the Cosmic Dawn with the Square Kilometre Array (2012, methodology): “The work of McQuinn et al. (2006) and Mao et al. (2008) considered the separation of the different Pµ terms in Equation 7.”
21 cm cosmology in the 21st century (2011, background): “Modelling of the ionization power spectrum need only degrade cosmological constraints by factors of a few [151].”
Inflation and the scale dependent spectral index: prospects and strategies (2010, methodology): “It was shown in [74] that the two most important limiting factors for 21 cm observations are, respectively, modeling of the contribution to the power spectrum from ionization fluctuations and foregrounds.”
A simulation-calibrated limit on the H i power spectrum from the GMRT Epoch of Reionization experiment (2013, background): “The distribution during the transition can be used to constrain cosmological parameters (McQuinn et al. 2006; Cooray, Li & Melchiorri 2008; Mao et al. 2008; Furlanetto et al. 2009; Pandolfi et al. 2011) and deduce the nature of the first ionizing sources themselves (Datta et al. 2012; Iliev et al.…”
The GMRT Epoch of Reionization experiment: a new upper limit on the neutral hydrogen power spectrum at z≈ 8.6 (2010, background): “In the future 21 cm tomography has the potential to add strong constraints on cosmological parameters (e.g., McQuinn et al. 2006; Cooray et al. 2008; Mao et al. 2008; Furlanetto et al. 2009; Masui et al. 2010).”
LATE-TIME COSMOLOGY WITH 21 cm INTENSITY MAPPING EXPERIMENTS (2014, background): “…survey extremely large volumes (Battye et al. 2004, 2013; McQuinn et al. 2006; Loeb & Wyithe 2008; Pritchard & Loeb 2008; Wyithe & Loeb 2008; Chang et al. 2008; Mao et al. 2008; Wyithe et al. 2008; Peterson et al. 2009; Bagla et al. 2010; Seo et al. 2010; Lidz et al. 2011; Ansari et al. 2012).”
MEASUREMENT OF 21 cm BRIGHTNESS FLUCTUATIONS AT z ∼ 0.8 IN CROSS-CORRELATION (2012, background): “…redshift range, one can nonetheless pursue three-dimensional (3D) intensity mapping (Chang et al. 2008; Loeb and Wyithe 2008; Ansari et al. 2012; Mao et al. 2008; 1 Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George St., Toronto, Ontario, M5S 3H8 2 Department…”
Prospects for cosmological collider physics (2016, background): “The largest observable modes kmin are limited by the survey volume only, which we take to cover the redshift range z = 30 to z = 100, ignoring possible foreground contamination at low k [55, 56].”
Neutrino Mass in Cosmology: Status and Prospects (2011, methodology): “003 eV, which would enable one to probe even the individual neutrino mass [92, 93].”
Reionization and Cosmology with 21-cm Fluctuations (2009, methodology): “Indeed, Mao et al. (2008) show that parameterization of the ionizations structure may provide constraints on the cosmology that are almost as tight as a case where 21 cm tomography measures the matter PS directly.”
Standard Model—axion—seesaw—Higgs portal inflation. Five problems of particle physics and cosmology solved in one stroke (2016, background): “Also, according to [126], the running of the scalar spectral index might be measured with an absolute error of 10−4 with 21 cm tomography.”
An efficient implementation of massive neutrinos in non-linear structure formation simulations (2012, background): “In addition, future measurements of CMB lensing (Hall & Challinor 2012) and 21 cm surveys (Mao et al. 2008) have the potential to reach yet lower bounds.”