Predictions for BAO distance estimates from the cross-correlation of the Lyman-alpha forest and redshifted 21-cm emission

Abstract

We investigate the possibility of using the cross-correlation of the Lyman-alpha forest and redshifted 21-cm emission to detect the baryon acoustic oscillation (BAO). The standard Fisher matrix formalism is used to determine the accuracy with which it will be possible to measure cosmological distances using this signal. Earlier predictions indicate that it will be possible to measure the dilation factor D_V with 1.9 % accuracy at z=2.5 from the BOSS Lyman-alpha forest auto-correlation. In this paper we investigate if it is possible to improve the accuracy using the cross-correlation. We use a simple parametrization of the Lyman-alpha forest survey which very loosely matches some properties of BOSS and predicts delta D_V/D_V = 2.0 % for the auto-correlation at z=2.5. For the redshifted 21-cm observations we consider individual antennas of size 2 m * 2 m distributed such that the baselines within 250 m are uniformly sampled. It is assumed that the observations span z=2 to 3 and covers the 10,000 deg^2 sky coverage of BOSS. We find that for 2 years of observation with an array of 2,000 antennas, the cross-correlation is 1.7 times more sensitive than the Lyman-alpha forest auto-correlation. The cross-correlation is 2.7 times more sensitive than the auto-correlation if we have 4,000 antennas and 4 years of observation. In conclusion, we find that it is possible to significantly increase the accuracy of the distance estimates by considering the cross-correlation signal.

Accepted for publication in JCAP. arXiv admin note: substantial text overlap with arXiv:1112.0745

References in corpus (12)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Cosmology at Low Frequencies: The 21 cm Transition and the High-Redshift Universe
• Baryon Acoustic Oscillations in the Ly-α forest of BOSS quasars
• Baryon Acoustic Oscillation Intensity Mapping as a Test of Dark Energy
• Dark energy and curvature from a future baryonic acoustic oscillation survey using the Lyman-alpha forest
• An improved measurement of the flux distribution of the Ly-alpha forest in QSO absorption spectra: the effect of continuum fitting, metal contamination and noise properties
• Clustering Analyses of 300,000 Photometrically Classified Quasars--II. The Excess on Very Small Scales
• The multi-frequency angular power spectrum of the epoch of reionization 21 cm signal
• A Spectroscopic Survey of Faint Quasars in the SDSS Deep Stripe: I. Preliminary Results from the Co-added Catalog
• The Acoustic Peak in the Lyman Alpha Forest
• Tomography of the intergalactic medium with Ly-alpha forests in close QSO pairs
• Transverse and longitudinal correlation functions in the Intergalactic Medium from 32 close pairs of high-redshift quasars

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