The BINGO project

II. Instrument description

¹ Divisão de Astrofísica, Instituto Nacional de Pesquisas Espaciais – INPE, Av. dos Astronautas 1758, 12227-010 São José dos Campos, SP, Brazil
e-mail: ca.wuensche@inpe.br
² Centro de Gestão e Estudos Estratégicos SCS Qd 9, Lote C, Torre C s/n Salas 401 a 405, 70308-200 Brasília, DF, Brazil
³ Instituto de Física, Universidade de São Paulo, R. do Matão, 1371 – Butantã, 05508-09 São Paulo, SP, Brazil
⁴ Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
⁵ Instituto de Astrofísica de Canarias, 38200 La Laguna, Tenerife, Canary Islands, Spain
⁶ Departamento de Astrofísica, Universidad de La Laguna (ULL), 38206 La Laguna, Tenerife, Spain
⁷ Phase2 Microwave Ltd., Unit 1a, Boulton Rd, Pin Green Ind. Est., Stevenage SG1 4QX, UK
⁸ University College London, Gower Street, London WC1E 6BT, UK
⁹ Department of Physics and Electronics, Rhodes University, PO Box 94 Grahamstown 6140, South Africa
¹⁰ Unidade Acadêmica de Física, Universidade Federal de Campina Grande, R. Aprígio Veloso, Bodocongó, 58429-900 Campina Grande, PB, Brazil
¹¹ Departamento de Física, Universidade Federal da Paraíba, Caixa Postal 5008, 58051-970 João Pessoa, Paraíba, Brazil
¹² Center for Gravitation and Cosmology, YangZhou University, Yangzhou 224009, PR China
¹³ School of Aeronautics and Astronautics, Shanghai Jiao Tong University, Shanghai 200240, PR China
¹⁴ Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85748 Garching, Germany
¹⁵ Technische Universität München, Physik-Department T70, James-Franck-Strasse 1, 85748 Garching, Germany
¹⁶ Center for Theoretical Physics of the Universe, Institute for Basic Science (IBS), Daejeon 34126, Korea
¹⁷ MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
¹⁸ Laboratoire Astroparticule et Cosmologie (APC), CNRS/IN2P3, Université Paris Diderot, 75205 Paris Cedex 13, France
¹⁹ IRFU, CEA, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
²⁰ Dipartimento di Fisica, Università degli Studi di Roma Tor Vergata, Via della Ricerca Scientifica, 1, 00133 Roma, Italy
²¹ INFN Sez. di Roma 2, Via della Ricerca Scientifica, 1, 00133 Roma, Italy
²² Departamento de Engenharia Elétrica, Universidade Federal de Campina Grande, R. Aprígio Veloso, 58429-900 Campina Grande, PB, Brazil
²³ School of Chemistry and Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa
²⁴ NAOC-UKZN Computational Astrophysics Centre (NUCAC), University of KwaZulu-Natal, Durban 4000, South Africa
²⁵ IAS, Bat 121, Université Paris-Saclay, 91405 Orsay Cedex, France
²⁶ ETH Zürich, Institute for Particle Physics and Astrophysics, HIT J13.2, Wolfgang-Pauli-Strasse 27, 8093 Zürich, Switzerland
²⁷ School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, PR China
²⁸ Department of Astronomy, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, PR China
²⁹ Instituto de Física, Universidade de Brasília, Campus Universitário Darcy Ribeiro, 70910-900 Brasília, DF, Brazil

Received: 25 March 2021
Accepted: 18 October 2021

Abstract

Context. The measurement of diffuse 21-cm radiation from the hyperfine transition of neutral hydrogen (H I signal) in different redshifts is an important tool for modern cosmology. However, detecting this faint signal with non-cryogenic receivers in single-dish telescopes is a challenging task. The BINGO (Baryon Acoustic Oscillations from Integrated Neutral Gas Observations) radio telescope is an instrument designed to detect baryonic acoustic oscillations (BAOs) in the cosmological H I signal, in the redshift interval 0.127 ≤ z ≤ 0.449.

Aims. This paper describes the BINGO radio telescope, including the current status of the optics, receiver, observational strategy, calibration, and the site.

Methods. BINGO has been carefully designed to minimize systematics, being a transit instrument with no moving dishes and 28 horns operating in the frequency range 980 ≤ ν ≤ 1260 MHz. Comprehensive laboratory tests were conducted for many of the BINGO subsystems and the prototypes of the receiver chain, horn, polarizer, magic tees, and transitions have been successfully tested between 2018–2020. The survey was designed to cover ∼13% of the sky, with the primary mirror pointing at declination δ = −15°. The telescope will see an instantaneous declination strip of 14.75°.

Results. The results of the prototype tests closely meet those obtained during the modeling process, suggesting BINGO will perform according to our expectations. After one year of observations with a 60% duty cycle and 28 horns, BINGO should achieve an expected sensitivity of 102 μK per 9.33 MHz frequency channel, one polarization, and be able to measure the H I power spectrum in a competitive time frame.