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arXiv · 1703.00634

Fisher Matrix Based Predictions for Measuring the z = 3.35 Binned 21-cm Power Spectrum using the Ooty Wide Field Array (OWFA)

Anjan Kumar Sarkar·Somnath Bharadwaj·Sk. Saiyad Ali
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Abstract

We use the Fisher matrix formalism to predict the prospects of measuring the redshifted 21-cm power spectrum in different $k$-bins using observations with the upcoming Ooty Wide Field Array (OWFA) which will operate at $326.5 {\rm MHZ}$. This corresponds to neutral hydrogen (HI) at $z=3.35$, and a measurement of the 21-cm power spectrum provides an unique method to probe the large-scale structures at this redshift. Our analysis indicates that a $5 σ$ detection of the binned power spectrum is possible in the $k$ range $0.05 \leq k \leq 0.3 \, {\rm Mpc}^{-1}$ with $1,000$ hours of observation. We find that the Signal-to-Noise ratio (${\rm SNR}$) peaks in the $k$ range $0.1- 0.2\, {\rm Mpc}^{-1}$ where a $10 σ$ detection is possible with $2,000$ hours of observations. Our analysis also indicates that it is not very advantageous to observe much beyond $1,000$ hours in a single field of view as the ${\rm SNR}$ increases rather slowly beyond this in many of the small $k$-bins. The entire analysis reported here assumes that the foregrounds have been completely removed.

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Anjan Kumar Sarkar, Somnath Bharadwaj, Sk. Saiyad Ali. 2017-03-07. Fisher Matrix Based Predictions for Measuring the z = 3.35 Binned 21-cm Power Spectrum using the Ooty Wide Field Array (OWFA). https://doi.org/10.1007/s12036-017-9432-2

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