Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 2402.08659

A demonstration of the effect of fringe-rate filtering in the Hydrogen Epoch of Reionization Array delay power spectrum pipeline

Hugh Garsden·Philip Bull·Mike Wilensky·Zuhra Abdurashidova·Tyrone Adams·James E. Aguirre·Paul Alexander·Zaki S. Ali·Rushelle Baartman·Yanga Balfour·Adam P. Beardsley·Lindsay M. Berkhout·Gianni Bernardi·Tashalee S. Billings·Judd D. Bowman·Richard F. Bradley·Jacob Burba·Steven Carey·Chris L. Carilli·Kai-Feng Chen·Carina Cheng·Samir Choudhuri·David R. DeBoer·Eloy de Lera Acedo·Matt Dexter·Joshua S. Dillon·Scott Dynes·Nico Eksteen·John Ely·Aaron Ewall-Wice·Nicolas Fagnoni·Randall Fritz·Steven R. Furlanetto·Kingsley Gale-Sides·Bharat Kumar Gehlot·Abhik Ghosh·Brian Glendenning·Adelie Gorce·Deepthi Gorthi·Bradley Greig·Jasper Grobbelaar·Ziyaad Halday·Bryna J. Hazelton·Jacqueline N. Hewitt·Jack Hickish·Tian Huang·Daniel C. Jacobs·Alec Josaitis·Austin Julius·MacCalvin Kariseb·Nicholas S. Kern·Joshua Kerrigan·Honggeun Kim·Piyanat Kittiwisit·Saul A. Kohn·Matthew Kolopanis·Adam Lanman·Paul La Plante·Adrian Liu·Anita Loots·Yin-Zhe Ma·David H. E. MacMahon·Lourence Malan·Cresshim Malgas·Keith Malgas·Bradley Marero·Zachary E. Martinot·Andrei Mesinger·Mathakane Molewa·Miguel F. Morales·Tshegofalang Mosiane·Steven G. Murray·Abraham R. Neben·Bojan Nikolic·Chuneeta Devi Nunhokee·Hans Nuwegeld·Aaron R. Parsons·Robert Pascua·Nipanjana Patra·Samantha Pieterse·Yuxiang Qin·Eleanor Rath·Nima Razavi-Ghods·Daniel Riley·James Robnett·Kathryn Rosie·Mario G. Santos·Peter Sims·Saurabh Singh·Dara Storer·Hilton Swarts·Jianrong Tan·Nithyanandan Thyagarajan·Pieter van Wyngaarden·Peter K. G. Williams·Zhilei Xu·Haoxuan Zheng
View original source ↗Read source document ↗Export metadata ↓

Abstract

Radio interferometers targeting the 21cm brightness temperature fluctuations at high redshift are subject to systematic effects that operate over a range of different timescales. These can be isolated by designing appropriate Fourier filters that operate in fringe-rate (FR) space, the Fourier pair of local sidereal time (LST). Applications of FR filtering include separating effects that are correlated with the rotating sky vs. those relative to the ground, down-weighting emission in the primary beam sidelobes, and suppressing noise. FR filtering causes the noise contributions to the visibility data to become correlated in time however, making interpretation of subsequent averaging and error estimation steps more subtle. In this paper, we describe fringe rate filters that are implemented using discrete prolate spheroidal sequences, and designed for two different purposes -- beam sidelobe/horizon suppression (the `mainlobe' filter), and ground-locked systematics removal (the `notch' filter). We apply these to simulated data, and study how their properties affect visibilities and power spectra generated from the simulations. Included is an introduction to fringe-rate filtering and a demonstration of fringe-rate filters applied to simple situations to aid understanding.

Explore related subjects

astro-ph.COastro-ph.IM

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Hugh Garsden, Philip Bull, Mike Wilensky, Zuhra Abdurashidova, Tyrone Adams, James E. Aguirre, Paul Alexander, Zaki S. Ali, Rushelle Baartman, Yanga Balfour, Adam P. Beardsley, Lindsay M. Berkhout, Gianni Bernardi, Tashalee S. Billings, Judd D. Bowman, Richard F. Bradley, Jacob Burba, Steven Carey, Chris L. Carilli, Kai-Feng Chen, Carina Cheng, Samir Choudhuri, David R. DeBoer, Eloy de Lera Acedo, Matt Dexter, Joshua S. Dillon, Scott Dynes, Nico Eksteen, John Ely, Aaron Ewall-Wice, Nicolas Fagnoni, Randall Fritz, Steven R. Furlanetto, Kingsley Gale-Sides, Bharat Kumar Gehlot, Abhik Ghosh, Brian Glendenning, Adelie Gorce, Deepthi Gorthi, Bradley Greig, Jasper Grobbelaar, Ziyaad Halday, Bryna J. Hazelton, Jacqueline N. Hewitt, Jack Hickish, Tian Huang, Daniel C. Jacobs, Alec Josaitis, Austin Julius, MacCalvin Kariseb, Nicholas S. Kern, Joshua Kerrigan, Honggeun Kim, Piyanat Kittiwisit, Saul A. Kohn, Matthew Kolopanis, Adam Lanman, Paul La Plante, Adrian Liu, Anita Loots, Yin-Zhe Ma, David H. E. MacMahon, Lourence Malan, Cresshim Malgas, Keith Malgas, Bradley Marero, Zachary E. Martinot, Andrei Mesinger, Mathakane Molewa, Miguel F. Morales, Tshegofalang Mosiane, Steven G. Murray, Abraham R. Neben, Bojan Nikolic, Chuneeta Devi Nunhokee, Hans Nuwegeld, Aaron R. Parsons, Robert Pascua, Nipanjana Patra, Samantha Pieterse, Yuxiang Qin, Eleanor Rath, Nima Razavi-Ghods, Daniel Riley, James Robnett, Kathryn Rosie, Mario G. Santos, Peter Sims, Saurabh Singh, Dara Storer, Hilton Swarts, Jianrong Tan, Nithyanandan Thyagarajan, Pieter van Wyngaarden, Peter K. G. Williams, Zhilei Xu, Haoxuan Zheng. 2025-07-07. A demonstration of the effect of fringe-rate filtering in the Hydrogen Epoch of Reionization Array delay power spectrum pipeline. https://arxiv.org/abs/2402.08659

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

From quantum fluctuations to galaxy power spectrum multipoles

These notes trace large-scale structure from primordial curvature perturbations generated by inflationary quantum fluctuations to galaxy power-spectrum multipoles. Three core lectures develop the linear matter power spectrum, spherical and anisotropic collapse, galaxy bias, redshift-space distortions, the Kaiser model, and multipole estimators with Gaussian covariance. The extension develops nonlinear bias and the one-loop effective field theory model used in full-shape analyses. Derivations are explicit; appendices collect longer calculations and solutions. The core lectures assume undergraduate-level cosmology; the extension assumes familiarity with perturbation theory.

astro-ph.CO↗
arXiv2026

A universal connection between lens density profiles and low-frequency wave optics in gravitational-wave lensing

We investigate the low-frequency behavior of the amplification factor in gravitational lensing and explore how it encodes information about the density profile of the lensing object. We derive the low-frequency expansion of the amplification factor under the Born approximation for a broad class of projected density profiles. For spherically symmetric profiles that decay faster than any power law at large distances, we derive a systematic expansion of the amplification factor in powers of frequency, with the logarithmic dependence appearing only in the leading term, and show that each expansion coefficient is determined by a finite set of moments of the density profile. We then extend the analysis to profiles with power-law tails and demonstrate that such profiles induce additional non-analytic frequency dependences, including fractional powers and logarithmic terms, which directly reflect the asymptotic behavior of the density distribution. Furthermore, we investigate the effects of non-sphericity and show that contributions from the quadrupole moment appear only as higher-order corrections relative to the spherically symmetric component in the low-frequency regime. Finally, we investigate the validity of the Born approximation in the low-frequency expansion. We derive a criterion for the maximum order of the low-frequency expansion up to which the Born approximation remains dominant over the post-Born corrections.

astro-ph.CO↗
arXiv2026

Initial clustering of primordial black holes: A general formulation for arbitrary local non-Gaussianity

Initial spatial clustering of primordial black holes (PBHs) induced by local-type non-Gaussianity (LNG) can substantially modify cosmological constraints on PBH abundance. Several inflationary scenarios that enhance curvature perturbations at small scales relevant to PBH formation predict LNG that is not necessarily perturbative. Therefore, it is crucial to establish a theoretical framework capable of investigating the initial clustering induced by arbitrary LNG. Here, we present a general analytical formulation for the PBH two-point correlation function applicable to arbitrary LNGs in the alternative approach. Under the assumptions that PBHs form only at the large peaks of perturbations, and that large-scale modes weakly modulate the local variance of small-scale perturbations, we derive an analytic expression for the PBH bias parameter, directly connecting initial clustering to the primordial trispectrum in the collapsed limit. We demonstrate the versatility of our formula by computing the bias parameters in the ultra-slow-roll inflation, curvaton, and modulated reheating scenarios. We also formally generalize the framework to broad power spectra to account for correlations across different PBH mass scales. Because our formulation does not rely on weak or perturbative non-Gaussianity assumptions, our result provides a universal theoretical basis for evaluating initial clustering impact on PBH observables.

astro-ph.CO↗