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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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Werner Eissner (1930–2022): a pioneer in computational atomic physics
(Atoms, 2023)Werner Eissner (Figure 1), a pioneer in computational atomic physics, was born on 16 October 1930 in the city of Görlitz, Germany, to Bernhard and Frieda (née Eckert) Eissner. He lost both parents early in life, his father ... -
The bright extragalactic ALMA redshift survey (BEARS) – II. Millimetre photometry of gravitational lens candidates
(Oxford University Press, 2023)We present 101- and 151-GHz ALMA continuum images for 85 fields selected from Herschel observations that have 500-μm flux densities >80 mJy and 250–500-μm colours consistent with z > 2, most of which are expected to be ... -
Spectral age distribution for radio-loud active galaxies in the XMM-LSS field
(Monthly Notices of the Royal Astronomical Society, 2023)Jets of energetic particles, as seen in FR type-I and FR type-II sources, ejected from the centre of radio-loud AGN affect the sources surrounding the intracluster medium/intergalactic medium. Placing constraints on the ... -
Non-booking for antenatal care and risks for vertical HIV transmission among women in Chitungwiza, Zimbabwe: a cross-sectional study
(BMC Pregnancy and Childbirth, 2022)Background: The success of prevention of mother to child transmission of HIV (PMTCT) programs dependents on pregnant women accessing antenatal care (ANC) services. Failure to access ANC throughout the course of pregnancy ... -
Hydra ii: Characterisation of Aegean, Caesar, profound, pybdsf, and selavy source finders
(Cambridge University Press, 2023)We present a comparison between the performance of a selection of source finders using a new software tool called Hydra. The companion paper, Paper I, introduced the Hydra tool and demonstrated its performance using ... -
Hydra I: An extensible multi-source-finder comparison and cataloguing tool
(Cambridge University Press, 2023)The latest generation of radio surveys are now producing sky survey images containing many millions of radio sources. In this context it is highly desirable to understand the performance of radio image source finder (SF) ... -
The lofar two-metre sky survey: Deep fields data release 1. V. Survey description, source classifications, and host galaxy properties
(Oxford University Press, 2023)Source classifications, stellar masses, and star-formation rates are presented for ≈80 000 radio sources from the first data release of the Low Frequency Array Two-metre Sky Survey (LoTSS) Deep Fields, which represents the ... -
The fore ground transfer function for H I intensity mapping signal reconstruction: MeerKLASS and precision cosmology applications
(Oxford University Press, 2023)Blind cleaning methods are currently the preferred strategy for handling foreground contamination in single-dish H I intensity mapping surv e ys. Despite the increasing sophistication of blind techniques, some signal loss ... -
Intrinsic scatter of caustic masses and hydrostatic bias: An observational study
(EDP Sciences, 2017)All estimates of cluster mass have some intrinsic scatter and perhaps some bias with true mass even in the absence of measurement errors for example caused by cluster triaxiality and large scale structure. Knowledge of ... -
Facile synthesis of NiSe2:α-Fe2O3 thin film: physical, optical and photoelectronic properties
(Thin Solid Films, 2023)In this study, a highly scalable approach to fabricating NiSe2:α-Fe2O3 heterojunction thin film in the absence of a dehydration step or lattice parameter matching was established. The attachment of NiSe2 to α-Fe2O3 leads ... -
Redshift evolution of galaxy group X-ray properties in the SIMBA simulations
(Oxford University Press, 2023)We examine the evolution of intragroup gas rest-frame X-ray scaling relations for group-sized haloes (M500 = 1012.3–1015 M) in the SIMBA galaxy formation simulation. X-ray luminosity LX versus M500 shows increasing deviation ... -
New constraints on primordial features from the galaxy two-point correlation function
(Physical Review, 2023)Features in the primordial power spectrum represent the imprinted signal in the density perturbations of the physics and evolution of the early Universe. A measurement of such signals will represents the need to go beyond ... -
A new technique to isolate kinematically anomalous gas in HI data cubes
(Oxford University Press, 2023)H I line observations of nearby galaxies often reveal the presence of extraplanar and/or kinematically anomalous gas that deviates from the general circular flow. In this work, we study the dependence of kinematically ... -
Chirality and octupole correlations in As-74
(Physical Review C, 2022)High-spin states in 74As were studied using the 74Ge(4He, 1p3n) reaction at beam energies of 58.6 and 62.6 MeV. Two positive- and one negative-parity bands have been identified in 74As. The two positive-parity bands ... -
Galaxy–galaxy lensing in the voice deep survey
(EDP Sciences, 2022)The multi-band photometry of the VOICE imaging data, overlapping with 4.9 deg2 of the Chandra Deep Field South (CDFS) area, enables both shape measurement and photometric redshift estimation to be the two essential ... -
Collective rotational bands at low excitation energy in 186Os: Vibrational and rotational degrees of freedom
(American Physical Society, 2022)Collective structures in 186Os have been investigated through the 186W(4He, 4n) 186Os reaction, at a beam energy of 48 MeV. The low-lying bands built on the excited 0+ 2 , 2+ 2 , and 4+ 3 states have been extended up ... -
Hot white dwarfs and pre-white dwarfs discovered with SALT
(Oxford University Press, 2023)The Southern African Large Telescope survey of helium-rich hot subdwarfs aims to explore evolutionary pathways among groups of highly evolved stars. The selection criteria mean that several hot white dwarfs and related ... -
Mightee: Deep 1.4 ghz source counts and the sky temperature contribution of star-forming galaxies and active galactic nuclei
(Oxford University Press, 2023)We present deep 1.4 GHz source counts from ∼5 deg2 of the continuum Early Science data release of the MeerKAT International Gigahertz Tiered Extragalactic Exploration survey down to S1.4GHz ∼15 μ Jy. Using observations ... -
Powder characteristics blending and microstructural analysis of a hot-pack rolled vacuum arc-melted gamma-tial-based sheet
(The Southern African Institute for Industrial Engineering, 2022)In the quest for cost-effective fabrication processes capable of producing sound γ-TiAl products, the microstructure and mechanical properties of a modified second-generation hot-rolled γ-TiAl-based alloy with nominal ... -
Effect of physical activity on coronary heart disease risk factors among firefighters: a scoping review protocol
(BMJ open, 2023)Introduction: Physical activity interventions have been used for various health conditions, including cardiovascular disease. However, the literature is still limited regarding the effect of physical activity on coronary ...
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