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The SARAO MeerKAT 1.3 GHz Galactic Plane Survey

We present the SARAO MeerKAT Galactic Plane Survey (SMGPS), a 1.3 GHz continuum survey of almost half of the Galactic Plane ($251^\circ \le l \le 358^\circ$ and $2^\circ \le l \le 61^\circ$ at $|b| \le 1.5^\circ$). SMGPS is the largest,…

Morphological classification of Radio Galaxies using Semi-Supervised Group Equivariant CNNs

Conference, Galactic and extragalactic astronomy, Interdisciplinary astronomy, Journal

Out of the estimated few trillion galaxies, only around a million have been detected through radio frequencies, and only a tiny fraction, approximately a thousand, have been manually classified. We have addressed this disparity between labeled…

Mining mini-halos with MeerKAT I. Calibration and imaging

Galactic and extragalactic astronomy, Journal, Observational astronomy

Radio mini-halos are clouds of diffuse, low-surface brightness synchrotron emission that surround the Brightest Cluster Galaxy (BCG) in massive cool-core galaxy clusters. In this paper, we use third generation calibration (3GC), also called…

The 1.28 GHz MeerKAT Galactic Center Mosaic

Galactic and extragalactic astronomy, Journal, Observational astronomy

The inner $\sim 200$ pc region of the Galaxy contains a 4 million $M_\odot$ supermassive black hole (SMBH), significant quantities of molecular gas, and star formation and cosmic-ray energy densities that are roughly two orders of magnitude…

Primary beam effects of radio astronomy antennas – II. Modelling MeerKAT L-band beams

Journal, Observational astronomy

After a decade of design and construction, South Africa’s SKA-MID precursor MeerKAT has begun its science operations. To make full use of the widefield capability of the array, it is imperative that we have an accurate model of the primary…

Constraining the intergalactic medium at z ≈ 9.1 using LOFAR Epoch of Reionization observations

Cosmology, Journal, Observational astronomy

We derive constraints on the thermal and ionization states of the intergalactic medium (IGM) at redshift $\approx 9.1$ using new upper limits on the 21-cm power spectrum measured by the LOFAR radio telescope and a prior on the ionized fraction…

Improved upper limits on the 21 cm signal power spectrum of neutral hydrogen at z ≈ 9.1 from LOFAR

Cosmology, Journal, Observational astronomy

A new upper limit on the 21 cm signal power spectrum at a redshift of $z \approx 9.1$ is presented, based on 141 h of data obtained with the Low-Frequency Array (LOFAR). The analysis includes significant improvements in spectrally smooth…

The 1.28 GHz MeerKAT DEEP2 Image

Galactic and extragalactic astronomy, Journal, Observational astronomy

We present the confusion-limited 1.28 GHz MeerKAT DEEP2 image covering one $\theta_b\approx 68'$ FWHM primary-beam area with $\theta=7.6^{''}$ FWHM resolution and $\sigma_n=0.55\pm 0.01$ $\mu$Jy beam$^{-1}$ rms noise. Its J2000 center position…