2016/01/09 by Cathryn M. Trott, Bart Pindor, B. Pindor +72 · 1 citation
Mathematics · Physics and Astronomy · #Algorithm #Applied mathematics #Astrophysics #Astrophysics and Cosmic Phenomena #Computer science #Covariance #Estimation theory #Estimator #Galaxies: Formation, Evolution, Phenomena #Galaxy #Mathematics #Physics #Radio Astronomy Observations and Technology #Redshift #Reionization #Spectral density #Statistics #astro-ph.CO #astro-ph.IM
paper · pdf · doi:10.3847/0004-637x/818/2/139
34 pages, accepted for publication in ApJ
arxiv created 2016/01/09 · openalex publication_date 2016/02/17 · arxiv updated 2016/03/09 · openalex created_date 2021/02/01 · openalex updated_date 2026/08/05
ABSTRACT Detection of the cosmological neutral hydrogen signal from the Epoch of Reionization (EoR) and estimation of its basic physical parameters are principal scientific aims of many current low-frequency radio telescopes. Here we describe the Cosmological H i Power Spectrum Estimator (CHIPS), an algorithm developed and implemented with data from the Murchison Widefield Array, to compute the two-dimensional and spherically-averaged power spectrum of brightness temperature fluctuations. The principal motivations for CHIPS are the application of realistic instrumental and foreground models to form the optimal estimator, thereby maximizing the likelihood of unbiased signal estimation, and allowing a full covariant understanding of the outputs. CHIPS employs an inverse-covariance weighting of the data through the maximum likelihood estimator, thereby allowing use of the full parameter space for signal estimation (“foreground suppression”). We describe the motivation for the algorithm, implementation, application to real and simulated data, and early outputs. Upon application to a set of 3 hr of data, we set a 2 σ upper limit on the EoR dimensionless power at Mpc −1 of mK 2 in the redshift range z = [6.2–6.6], consistent with previous estimates.