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arXiv · 2607.09374

Overview of the Canadian Hydrogen Observatory and Radio Transient Detector (CHORD) Project

The CHORD Collaboration·Kevin Bandura·Leonid Belostotski·Lindsay Berkhout·Gianni Bernardi·Akanksha Bij·Duncan Cameron-Steinke·Arnab Chakraborty·Hsin Cynthia Chiang·Jean-Francois Cliche·Sophia Da Costa·Evan Davies-Velie·Matt Dobbs·Emmanuel Fonseca·Simon Foreman·Qwin Goodwin·Ian Hendricksen·Jason Hessels·Alex S. Hill·Mohammad Islam·Michael Jafs·Aditya Krishna Karigiri Madhusudhan·Gordon Lacy·Dustin Lang·Calvin Leung·Jessie Lin·Adrian Liu·Vincent MacKay·Kiyoshi W. Masui·Juan Mena-Parra·James Mertens·Daniele Michilli·Kenzie Nimmo·Robert Pascua·Maura Pilia·Andrea Possenti·Aniket Prasad·Andre Renard·Sophia D'Agostino Rubens·Mawson Sammons·Erik Schnetter·Paul Scholz·Seth Siegel·Jonathan Sievers·Kendrick Smith·Kristine Spekkens·Shronim Tiwari·Martin Topinka·Matteo Trudu·Keith Vanderlinde·Dallas Wulf·Yifan Zhao
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Abstract

The Canadian Hydrogen Observatory and Radio-transient Detector (CHORD) is a next-generation wideband radio interferometer currently being constructed and commissioned at the Dominion Radio Astrophysical Observatory in British Columbia, Canada. CHORD is designed for precision 21\,cm cosmology, fast radio transient discovery, spectral line galaxy surveys, and pulsar science using a highly redundant large-N, small-diameter drift-scan array architecture. The telescope consists of a 512-element core array of 6\,m dishes operating from 300--1500\,MHz in drift-scan mode, together with two 64-dish outrigger stations located at the Hat Creek Radio Observatory and the Green Bank Observatory for long-baseline transient localization. The instrument supports multiple simultaneous digital backends for interferometric correlation, FRB detection, pulsar beamforming, and high spectral resolution surveys. CHORD is designed with an emphasis on precision beam control and stable instrumental response, incorporating lessons learned from the Canadian Hydrogen Intensity Mapping Experiment (CHIME) while providing a substantial increase in sensitivity. Initial performance has been evaluated using a three-dish engineering array, and a 64-dish pathfinder array is currently being commissioned. The full array will be commissioned in 2028.

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The CHORD Collaboration, Kevin Bandura, Leonid Belostotski, Lindsay Berkhout, Gianni Bernardi, Akanksha Bij, Duncan Cameron-Steinke, Arnab Chakraborty, Hsin Cynthia Chiang, Jean-Francois Cliche, Sophia Da Costa, Evan Davies-Velie, Matt Dobbs, Emmanuel Fonseca, Simon Foreman, Qwin Goodwin, Ian Hendricksen, Jason Hessels, Alex S. Hill, Mohammad Islam, Michael Jafs, Aditya Krishna Karigiri Madhusudhan, Gordon Lacy, Dustin Lang, Calvin Leung, Jessie Lin, Adrian Liu, Vincent MacKay, Kiyoshi W. Masui, Juan Mena-Parra, James Mertens, Daniele Michilli, Kenzie Nimmo, Robert Pascua, Maura Pilia, Andrea Possenti, Aniket Prasad, Andre Renard, Sophia D'Agostino Rubens, Mawson Sammons, Erik Schnetter, Paul Scholz, Seth Siegel, Jonathan Sievers, Kendrick Smith, Kristine Spekkens, Shronim Tiwari, Martin Topinka, Matteo Trudu, Keith Vanderlinde, Dallas Wulf, Yifan Zhao. 2026-07-10. Overview of the Canadian Hydrogen Observatory and Radio Transient Detector (CHORD) Project. https://arxiv.org/abs/2607.09374

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