MIGHTEE

MIGHTEE
Name	MIGHTEE
Organization	South African Radio Astronomy Observatory
Type	Radio continuum and spectral line survey
Location	MeerKAT
Wavelength	Radio (1.0–1.7 GHz)
Status	Ongoing

MIGHTEE

MIGHTEE is a deep radio continuum and spectral-line survey designed to exploit the sensitivity and imaging fidelity of MeerKAT to study galaxy evolution, magnetic fields, and neutral hydrogen. Conceived within the context of large survey projects alongside LADUMA, MALS, and EMU, the program targets legacy science across cosmology, galaxy formation, and active galactic nuclei using multiwavelength synergies with facilities such as Hubble Space Telescope, Spitzer Space Telescope, Chandra X‑ray Observatory, and ALMA. The project is coordinated through the South African Radio Astronomy Observatory and involves a broad consortium spanning institutions like University of Cape Town, University of Oxford, National Radio Astronomy Observatory, and Max Planck Institute for Radio Astronomy.

Overview

MIGHTEE surveys several extragalactic deep fields including areas overlapping with COSMOS, XMM-Newton, ELAIS-S1, and VIDEO. It collects continuum and polarimetric data across the L‑band using arrays of dishes at the Karoo site, providing sensitivity suited to detect star formation and active nuclei out to intermediate redshift ranges where surveys such as SDSS, GAMA, and VIPERS provide complementary spectroscopy. The survey design emphasizes commensal observations that complement spectral-line efforts in programs like LADUMA and imaging campaigns tied to VISTA, CFHT, Subaru Telescope, and Keck Observatory.

Scientific goals

MIGHTEE aims to measure cosmic star-formation history by detecting faint radio emission from star-forming galaxies and disentangling contributions from Seyfert galaxies, Quasars, and radio‑quiet AGN populations. It targets evolution of the radio luminosity function to connect with surveys led by Herschel Space Observatory and Planck, probe magnetism via Faraday rotation measures to study magnetoionic media in objects like M82 analogs and cluster systems such as Coma Cluster and Perseus Cluster, and constrain baryonic feedback tied to feedback processes invoked in simulations by teams at Max Planck Institute for Astrophysics and Flatiron Institute. The survey also provides inputs for cosmological probes using cross-correlations with datasets from Planck, DES, and Euclid.

Survey design and observations

Observations use the MeerKAT 64-dish configuration with L‑band receivers and bandwidth chosen to optimize continuum sensitivity and HI spectral-line capability in commensal modes. Fields were selected for extensive multiwavelength coverage, overlapping legacy fields such as COSMOS, ELAIS-N1, and Lockman Hole and leveraging photometric catalogs from GALEX, WISE, VIKING, and spectroscopic redshifts from DEEP2, VVDS, and zCOSMOS. Observing strategy includes deep pointings with long integrations and mosaics to achieve sub‑microjansky rms thresholds in continuum and competitive column density sensitivity for HI stacking studies employed by groups at University of Manchester and CSIRO. Calibration strategies reference flux density scales tied to measurements by Perley–Butler standards and polarization calibration informed by observations of sources like 3C 286 and PKS 1934-638.

Data processing and products

Raw visibilities are processed through pipelines developed by the consortium, incorporating tools such as CASA, CARTA, and custom software from the South African Radio Astronomy Observatory. Imaging uses wideband multi‑frequency synthesis, direction‑dependent calibration, and polarization decomposition to produce continuum maps, spectral cubes, rotation measure synthesis products, and source catalogs cross-matched to ancillary databases including GAIA, Pan-STARRS, and HST catalogs. Public data releases supply calibrated visibilities, Stokes IQUV images, HI cubes, and value‑added catalogs with redshifts and multiwavelength identifications used by analysis teams at University of Cape Town, University of Western Cape, and University of Cambridge.

Key results and discoveries

MIGHTEE has produced constraints on faint radio source counts that inform models developed by researchers at NRAO and Jodrell Bank Observatory, revealed populations of radio‑intermediate AGN overlapping with X‑ray selected Seyfert galaxies and LINERs identified in Chandra catalogs, and measured rotation measures that map magnetic field structure in group and cluster environments in studies related to Perseus Cluster physics. The survey enabled HI stacking analyses that probe neutral gas reservoirs in massive galaxies complementary to single‑dish results from Arecibo Observatory and interferometric studies from VLA. Cross-correlation analyses with DES and Planck data have provided constraints on large‑scale bias and integrated Sachs‑Wolfe measurements, informing cosmological models pursued by teams within Institute of Astronomy, Cambridge and Harvard-Smithsonian Center for Astrophysics.

Collaborations and instrumentation

The collaboration includes institutions across Africa, Europe, North America, and Asia, notably the South African Radio Astronomy Observatory, University of Cape Town, University of Pretoria, University of Oxford, Durham University, INAF, NCRA-TIFR, and CSIRO. Instrumentation relies on the MeerKAT array and benefits from synergies with facilities such as ALMA, VLA, LOFAR, and optical/infrared observatories like Subaru Telescope and Very Large Telescope. The project interfaces with data archives and consortiums including the Square Kilometre Array pathfinder community and engages student and postdoctoral researchers through programs run by institutions like Max Planck Institute for Astronomy and University of Cape Town.

Category:Radio astronomy surveys