MHONGOOSE: A MeerKAT nearby galaxy H I survey

¹ Netherlands Institute for Radio Astronomy (ASTRON), Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands
e-mail: blok@astron.nl
² Dept. of Astronomy, Univ. of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
³ Kapteyn Astronomical Institute, University of Groningen, PO Box 800, 9700 AV Groningen, The Netherlands
⁴ INAF – Osservatorio Astronomico di Cagliari, Via della Scienza 5, 09047 Selargius, CA, Italy
⁵ Adjunct Astronomer, Green Bank Observatory, 155 Observatory Road, Green Bank, WV 24944, USA
⁶ Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
⁷ Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2, Canada
⁸ INAF – Padova Astronomical Observatory, Vicolo dell’Osservatorio 5, 35122 Padova, Italy
⁹ International Centre for Radio Astronomy Research, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
¹⁰ Argelander-Institut für Astronomie, Auf dem Hügel 71, 53121 Bonn, Germany
¹¹ Instituto de Astrofísica, Departamento de Ciencias Físicas, Universidad Andrés Bello, Fernandez Concha 700, Las Condes, Santiago, Chile
¹² Department of Physics and Astronomy, 102 Natural Science Building, University of Louisville, Louisville, KY 40292, USA
¹³ Ruhr University Bochum, Faculty of Physics and Astronomy, Astronomical Institute (AIRUB), Universitätsstrasse 150, 44801 Bochum, Germany
¹⁴ Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
¹⁵ Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USA
¹⁶ Center for Cosmology and Astroparticle Physics, 191 West Woodruff Avenue, Columbus, OH 43210, USA
¹⁷ South African Astronomical Observatory (SAAO), PO Box 9, Observatory, 7935 Cape Town, South Africa
¹⁸ Southern African Larger Telescope (SALT), PO Box 9, Observatory, 7935 Cape Town, South Africa
¹⁹ Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE, UK
²⁰ Centre for Extragalactic Astronomy, Department of Physics, Durham University, South Road, Durham DH1 3LE, UK
²¹ Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany
²² Instituto de Astrofísica de Andalucía-CSIC, Glorieta de la Astronomía s/n, 18008 Granada, Spain
²³ CSIRO, Space & Astronomy, PO Box 1130, Bentley, WA 6102, Australia
²⁴ Laboratoire de Physique et de Chimie de l’Environnement, Observatoire d’Astrophysique de l’Université Ouaga I Pr Joseph KiZerbo (ODAUO), 03 BP 7021, Ouaga 03, Burkina Faso
²⁵ Observatoire de Paris, Collège de France, Université PSL, Sorbonne Université, CNRS, LERMA, Paris, France
²⁶ Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK
²⁷ E.A. Milne Centre for Astrophysics, University of Hull, Hull HU6 7RX, UK
²⁸ Department of Physics and Electronics, Rhodes University, PO Box 94, Makhanda 6140, South Africa
²⁹ Australia Telescope National Facility, CSIRO Astronomy and Space Science, PO Box 76, Epping, NSW 1710, Australia
³⁰ Western Sydney University, Locked Bag 1797, Penrith South, NSW 1797, Australia
³¹ Department of Astronomy, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
³² Department of Physics and Space Science, Royal Military College of Canada, PO Box 17000, Station Forces Kingston, ON K7K 7B4, Canada
³³ Department of Physics, Engineering Physics and Astronomy, Queen’s University, Kingston, ON K7L 3N6, Canada
³⁴ Max Planck Institute for Extraterrestrial Physics, Gießenbachstraße 1, 85748 Garching, Germany
³⁵ University of Wisconsin-Madison, Department of Astronomy, 475 N. Charter Street, Madison, WI 53706-1582, USA
³⁶ Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK
³⁷ Department of Physics and Astronomy, University of the Western Cape, Robert Sobukwe Rd, Bellville 7535, South Africa
³⁸ The Inter-University Institute for Data Intensive Astronomy (IDIA), University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
³⁹ National Radio Astronomy Observatory, PO Box O, Socorro, NM 87801, USA
⁴⁰ Department of Physics and Astronomy, MSC07 4220, 1 University of New Mexico, Albuquerque, NM 87131, USA
⁴¹ Centre for Space Research, North-West University, Potchefstroom 2520, South Africa
⁴² Department of Physics, Virginia Polytechnic Institute and State University, 50 West Campus Drive, Blacksburg, VA 24061, USA
⁴³ Wits Centre for Astrophysics, School of Physics, University of the Witwatersrand, 1 Jan Smuts Avenue, Johannesburg 2000, South Africa
⁴⁴ Department of Physics and Astronomy, Sejong University, Seoul 05006, South-Korea
⁴⁵ NASA Headquarters, 300 Hidden Figures Way, SE, Mary W. Jackson NASA HQ Building, Washington, DC 20546, USA
⁴⁶ School of Physics and Astronomy, Cardiff University, Queens Building, The Parade, Cardiff CF24 3AA, UK
⁴⁷ Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854-8019, USA
⁴⁸ Department of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK
⁴⁹ School of Mathematical and Physical Sciences, Macquarie University, Balaclava Road, North Ryde, Sydney, NSW 2109, Australia

Received: 17 October 2023
Accepted: 27 March 2024

Abstract

The MHONGOOSE (MeerKAT H I Observations of Nearby Galactic Objects: Observing Southern Emitters) survey maps the distribution and kinematics of the neutral atomic hydrogen (H I) gas in and around 30 nearby star-forming spiral and dwarf galaxies to extremely low H I column densities. The H I column density sensitivity (3σ over 16 km s⁻¹) ranges from ∼5 × 10¹⁷ cm⁻² at 90″ resolution to ∼4 × 10¹⁹ cm⁻² at the highest resolution of 7″. The H I mass sensitivity (3σ over 50 km s⁻¹) is ∼5.5 × 10⁵ M_⊙ at a distance of 10 Mpc (the median distance of the sample galaxies). The velocity resolution of the data is 1.4 km s⁻¹. One of the main science goals of the survey is the detection of cold accreting gas in the outskirts of the sample galaxies. The sample was selected to cover a range in H I masses from 10⁷ M_⊙ to almost 10¹¹ M_⊙ in order to optimally sample possible accretion scenarios and environments. The distance to the sample galaxies ranges from 3 to 23 Mpc. In this paper, we present the sample selection, survey design, and observation and reduction procedures. We compared the integrated H I fluxes based on the MeerKAT data with those derived from single-dish measurement and find good agreement, indicating that our MeerKAT observations are recovering all flux. We present H I moment maps of the entire sample based on the first ten percent of the survey data, and find that a comparison of the zeroth- and second-moment values shows a clear separation in the physical properties of the H I between areas with star formation and areas without related to the formation of a cold neutral medium. Finally, we give an overview of the H I-detected companion and satellite galaxies in the 30 fields, five of which have not previously been cataloged. We find a clear relation between the number of companion galaxies and the mass of the main target galaxy.