MIGHTEE-HI: The HI emission project of the MeerKAT MIGHTEE survey

TL;DR

The MIGHTEE-HI project uses MeerKAT to conduct a pioneering deep, blind survey of neutral hydrogen in galaxies up to redshift 0.6, enabling studies of galaxy evolution, environment effects, and low-mass populations.

Contribution

This is one of the first deep, medium-wide HI surveys with MeerKAT, extending HI observations to higher redshifts and providing new insights into galaxy evolution and environment effects.

Findings

Detected nearly 3000 galaxies in HI up to z=0.4

First kinematic models of individual sources from the survey

Sample includes galaxies with HI mass <10^8 Msun

Abstract

We present the HI emission project within the MIGHTEE survey, currently being carried out with the newly commissioned MeerKAT radio telescope. This is one of the first deep, blind, medium-wide interferometric surveys for neutral hydrogen (HI) ever undertaken, extending our knowledge of HI emission to z=0.6. The science goals of this medium-deep, medium-wide survey are extensive, including the evolution of the neutral gas content of galaxies over the past 5 billion years. Simulations predict nearly 3000 galaxies over 0<z<0.4 will be detected directly in HI, with statistical detections extending to z=0.6. The survey allows us to explore HI as a function of galaxy environment, with massive groups and galaxy clusters within the survey volume. Additionally, the area is large enough to contain as many as 50 local galaxies with HI mass $<10^8$ Msun, which allows us to study the low-mass galaxy population. The 20 deg$^2$ main survey area is centred on fields with exceptional multi-wavelength ancillary data, with photometry ranging from optical through far-infrared wavelengths, supplemented with multiple spectroscopic campaigns. We describe here the survey design and the key science goals. We also show first results from the Early Science observations, including kinematic modelling of individual sources, along with the redshift, HI, and stellar mass ranges of the sample to date.