Epoch of reionization window. I. Mathematical formalism
MetadataShow full item record
The 21 cm line provides a powerful probe of astrophysics and cosmology at high redshifts, but unlocking the potential of this probe requires the robust mitigation of foreground contaminants that are typically several orders of magnitude brighter than the cosmological signal. Recent simulations and observations have shown that the smooth spectral structure of foregrounds combines with instrument chromaticity to contaminate a “wedge”-shaped region in cylindrical Fourier space. While previous efforts have explored the suppression of foregrounds within this wedge, as well as the avoidance of this highly contaminated region, all such efforts have neglected a rigorous examination of the error statistics associated with the wedge. Using a quadratic estimator formalism applied to the interferometric measurement equation, we provide a framework for such a rigorous analysis (incorporating a fully covariant treatment of errors). Additionally, we find that there are strong error correlations at high spatial wave numbers that have so far been neglected in sensitivity derivations. These error correlations substantially degrade the sensitivity of arrays relying on contributions from long baselines, compared to what one would estimate assuming uncorrelated errors.
Showing items related by title, author, creator and subject.
McKnight, David (2011)Background: Medication Safety has become a major health issue in Australia and internationally. Medication use is a part of most people lives with around seven in ten Australians and nine in ten older Australians having ...
Alshemary, A.; Pramanik, Alokesh; Basak, A.; Littlefair, G. (2018)© 2018 Elsevier Ltd The present paper studies different types of errors generated on the feature (cylindrical holes) which was fabricated by the wire EDM of 2205 duplex stainless steel. Different experimental parameters ...
Han, Sangwon; Love, Peter; Peña-Mora, Feniosky (2013)Design errors leading to rework and/or design changes are considered to be the primary contributor to schedule delays and cost overruns in design and construction projects. While design errors are deemed prevalent, most ...