Publication Details

AFRICAN RESEARCH NEXUS

SHINING A SPOTLIGHT ON AFRICAN RESEARCH

earth and planetary sciences

Early observations of the MHONGOOSE galaxies: Getting ready for MeerKAT

Monthly Notices of the Royal Astronomical Society, Volume 482, No. 1, Year 2019

We present early observations of 20 galaxies in the MHONGOOSE survey galaxies using KAT-7, the GBT, and MeerKAT.We present the best calibrators for five of the MHONGOOSE galaxies observed with the KAT-7, and search for signs of gas accretion in the GBT data, down to 3σ column density levels of 2.2 × 1018 cm-2 over a 20 km s-1 line width, but identify none. Using the KAT-7 and MeerKAT data, we have derived rotation curves and mass models for NGC 3621 and NGC 7424, respectively, out to an unprecedented extent. As a precursor to the SKA, the MeerKAT telescope combines both a high spatial resolution and a large field of view, necessary to map the extended neutral hydrogen in local galaxies. The mass models of the two galaxies were constructed for both the Dark Matter (DM) models (the pseudoisothermal model and the Navarro-Frenk-White model) and MOND. Overall, we find that the DM models provide a better fit than MOND to the galaxies' rotation curves. Furthermore, the pseudo-isothermal model is found to be the most consistent with the observations.
Statistics
Citations: 12
Authors: 12
Affiliations: 8
Identifiers
Study Design
Cross Sectional Study
Study Approach
Quantitative