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Black Holes 'NSinc: The SA discovery that’s got astronomers in a spin
A deep scan of the sky in radio waves revealed something completely unexpected to South African astronomers: that somehow, and for some unexplained reason, supermassive black holes in one region of space are all releasing radio waves in the same direction. Could this be a vital clue in understanding how the universe was formed?
Astronomers Perplexed By Rare Alignment Of Supermassive Black Holes (Youtube video)
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First Observations of E-Region Near Range Echoes Partially Modulated by F-Region Traveling Ionospheric Disturbances Observed by the Same SuperDARN HF Radar
(Journal of Geophysical Research: Space Physics, 2022)We present the first observations from SuperDARN HF radar data of E-region Near Range Echoes (NREs) whose amplitudes are partially modulated by Medium-Scale Traveling Ionospheric Disturbances (MSTIDs) propagating in the ... -
Assessing accessibility and availability of portable water supply in selected communities of Lepelle-Nkumpi local municipality, Limpopo province of South Africa
(elsevier, 2022)In this study, we assessed the accessibility and availability of portable water supply in selected communities of the Lepelle-Nkumpi Local Municipality. A systematic random sampling method was used to select 49 households ... -
Deep extragalactic visible legacy survey (DEVILS):Evolution of the σsFR-M relation and implications for self-regulated star formation
(University of the Western Cape, 2022)We present the evolution of the star formation dispersion–stellar mass relation ( σSFR –M ) in the DEVILS D10 region using new measurements derived using the PROSPECT spectral energy distribution fitting code. We find ... -
A deep radio view of the evolution of the cosmic star formation rate density from a stellar-mass-selected sample in VLA-COSMOS
(University of the Western Cape, 2022)We present the 1.4 GHz radio luminosity functions (RLFs) of galaxies in the Cosmic Evolution Surv e y (COSMOS) field, measured abo v e and below the 5 σdetection threshold, using a Bayesian model-fitting technique. The ... -
Optimization of the observing cadence for the Rubin Observatory Legacy Survey of space and time: A pioneering process of community-focused experimental design
(University of the Western Cape, 2022)Vera C. Rubin Observatory is a ground-based astronomical facility under construction, a joint project of the National Science Foundation and the U.S. Department of Energy, designed to conduct a multipurpose 10 yr optical ... -
COSMOS2020: A panchromatic view of the universe to z ∼ 10 from two complementary catalogs
(University of the Western Cape, 2022)The Cosmic Evolution Survey (COSMOS) has become a cornerstone of extragalactic astronomy. Since the last public catalog in 2015, a wealth of new imaging and spectroscopic data have been collected in the COSMOS field. This ... -
Probing the nature of the conjectured low-spin wobbling bands in atomic nuclei
(Elsevier, 2022)The precession of an atomic nucleus can be approximately described as wobbling motion, arising from the coupling of a rotation and a harmonic vibration. Recently, a number of wobbling bands were reported at low spin, which ... -
Multimodality and new materialism in science learning: Exploring insights from an introductory physics lesson
(Unisa Press, 2021)Science disciplines are inherently multimodal, involving written and spoken language, bodily gestures, symbols, diagrams, sketches, simulation and mathematical formalism. Studies have shown that ... -
High Molecular-gas to Dust Mass Ratios Predicted in Most Quiescent Galaxies
(American Astronomical Society, 2021)Observations of cold molecular gas reservoirs are critical for understanding the shutdown of star formation in massive galaxies. While dust continuum is an efficient and affordable tracer, this method relies upon the ... -
SKAO HI intensity mapping: blind foreground subtraction challenge
(University of the Western Cape, 2022)Neutral Hydrogen Intensity Mapping (H I IM) surveys will be a powerful new probe of cosmology. However, strong astrophysical foregrounds contaminate the signal and their coupling with instrumental systematics further ... -
MIGHTEE: Total intensity radio continuum imaging and the COSMOS/XMM-LSS Early Science fields
(University of the Western Cape, 2022)MIGHTEE is a galaxy evolution survey using simultaneous radio continuum, spectropolarimetry, and spectral line observations from the South African MeerKAT telescope. When complete, the survey will image ∼20 deg2 over the ... -
The Copernican principle in light of the latest cosmological data
(University of the Western Cape, 2022)We pursue a program to confront observations with inhomogeneous extensions of the FLRW metric. The main idea is to test the Copernican principle (CP) rather than assuming it a priori. We consider the CDM model endowed with ... -
The MeerKAT Galaxy Cluster Legacy Survey: Survey overview and highlights
(University of the Western Cape, 2022)MeerKAT’s large number (64) of 13.5 m diameter antennas, spanning 8 km with a densely packed 1 km core, create a powerful instrument for wide-area surveys, with high sensitivity over a wide range of angular scales. The ... -
Automated Detection of Antenna Malfunctions in Large-N Interferometers: A Case Study With the Hydrogen Epoch of Reionization Array
(2022)We present a framework for identifying and flagging malfunctioning antennas in large radio interferometers. We outline two distinct categories of metrics designed to detect outliers along known failure modes of large ... -
Validation of the HERA Phase I Epoch of Reionization 21 cm Power Spectrum Software Pipeline
(The American Astronomical Society., 2022)We describe the validation of the HERA Phase I software pipeline by a series of modular tests, building up to an end-to-end simulation. The philosophy of this approach is to validate the software and algorithms used in ... -
HERA Phase I Limits on the Cosmic 21 cm Signal: Constraints on Astrophysics and Cosmology during the Epoch of Reionization
(The American Astronomical Society., 2022)Recently, the Hydrogen Epoch of Reionization Array (HERA) has produced the experiment’s first upper limits on the power spectrum of 21 cm fluctuations at z ∼ 8 and 10. Here, we use several independent theoretical models ... -
Superhorizon Perturbations: A Possible Explanation of the Hubble–Lemaître Tension and the Large-scale Anisotropy of the Universe.
(The American Astronomical Society., 2022)Current cosmological observations point to a serious discrepancy between the observed Hubble parameter obtained using direct versus cosmic microwave background radiation measurements. Besides this so-called Hubble– Lemaître ... -
Considerations for Optimizing the Photometric Classification of Supernovae from the Rubin Observatory
(The American Astronomical Society., 2022-01-18)The Vera C. Rubin Observatory will increase the number of observed supernovae (SNe) by an order of magnitude; however, it is impossible to spectroscopically confirm the class for all SNe discovered. Thus, photometric ... -
A deep radio view of the evolution of the cosmic star formation rate density from a stellar-mass-selected sample in VLA-COSMOS
(Royal Astronomical Society, 2022)We present the 1.4 GHz radio luminosity functions (RLFs) of galaxies in the Cosmic Evolution Survey (COSMOS) field, measured above and below the 5σ detection threshold, using a Bayesian model-fitting technique. The radio ... -
Analysis and exploitation of landforms for improved optimisation of camera based wildfire detection systems
(Springer, 2021)Tower-mounted camera-based wildfire detection systems provide an effective means of early forest fire detection. Historically, tower sites have been identified by foresters and locals with intimate knowledge of the terrain ...
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