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DOE OSTI · 2582058

MHONGOOSE: A MeerKAT nearby galaxy H I survey

Abstract

The MHONGOOSE (MeerKAT H IObservations 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 Icolumn densities. The H Icolumn density sensitivity (3σover 16 km s −1 ) ranges from ∼5 × 10 17 cm −2 at 90″ resolution to ∼4 × 10 19 cm −2 at the highest resolution of 7″. The H Imass sensitivity (3σover 50 km s −1 ) is ∼5.5 × 10 5 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 Imasses from 10 7 M ⊙ to almost 10 11 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 Ifluxes 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 Imoment 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 Ibetween 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.

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BibTeXRIS

de Blok, W. (ORCID:0000000189574518), Healy, J. (ORCID:0000000310208684), Maccagni, F. (ORCID:0000000299301844), Pisano, D., Bosma, A. (ORCID:0000000211286089), English, J. (ORCID:0000000153101022), Jarrett, T., Marasco, A., Meurer, G., Veronese, S., Bigiel, F., Chemin, L., Fraternali, F., Holwerda, B., Kamphuis, P., Klöckner, H. (ORCID:0000000206482704), Kleiner, D., Leroy, A., Mogotsi, M., Oman, K. (ORCID:0000000198577788), Schinnerer, E. (ORCID:0000000239337677), Verdes-Montenegro, L., Westmeier, T., Wong, O., Zabel, N., Amram, P., Carignan, C. (ORCID:0000000190896151), Combes, F. (ORCID:0000000326587893), Brinks, E. (ORCID:0000000277589699), Dettmar, R., Gibson, B., Jozsa, G., Koribalski, B., McGaugh, S., Oosterloo, T. (ORCID:0000000206166971), Spekkens, K., Schröder, A., Adams, E. (ORCID:0000000297985111), Athanassoula, E., Bershady, M. (ORCID:0000000231314374), Beswick, R., Blyth, S. (ORCID:0000000257770036), Elson, E., Frank, B., Heald, G., Henning, P., Kurapati, S., Loubser, S. (ORCID:0000000239377126), Lucero, D., Meyer, M., Namumba, B. (ORCID:0000000310328889), Oh, S., Sardone, A., Sheth, K., Smith, M., Sorgho, A. (ORCID:0000000252338260), Walter, F., Williams, T., Woudt, P. (ORCID:0000000268961655), Zijlstra, A.. 2024-08-01. MHONGOOSE: A MeerKAT nearby galaxy H I survey. https://doi.org/10.1051/0004-6361/202348297

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