Physics and Astronomy: Recent submissions
Now showing items 241-260 of 533
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Qualitatively different ways of unpacking visual representations when teaching intermolecular forces in upper secondary school
(Wiley, 2021)Since visual representations play a particularly important role in the teaching and learning of chemistry, the ex-ploration described in this article focuses on them. This is an explorative study of the qualitatively ... -
Oxazinethione derivatives as a precursor to pyrazolone and pyrimidine derivatives: Synthesis, biological activities, molecular modeling, adme, and molecular dynamics studies
(MDPI, 2021)In this study, we used oxazinethione as a perfect precursor to synthesize new pyrimidine and pyrazole derivatives with potent biological activities. Biological activities were determined for all compounds against A. flavus, ... -
Spectroscopy of states in Ba 136 using the Ba 138 (p,t) reaction
(American Physical Society, 2021)Background: The Ba136 isotope is the daughter nucleus in Xe136ββ decay. It also lies in a shape transitional region of the nuclear chart, making it a suitable candidate to test a variety of nuclear models. Purpose: To ... -
The origin of the dust extinction curve in milky way-like galaxies
(Oxford University Press, 2021)We develop a cosmological model for the evolution of dust grains in galaxies with a distribution of sizes in order to understand the origin of the Milky Way dust extinction curve. Our model considers the formation of active ... -
HELP: The Herschel Extragalactic Legacy Project
(Oxford University Press, 2021)We present the Herschel Extragalactic Legacy Project (HELP). This project collates, curates, homogenizes and creates derived data products for most of the premium multiwavelength extragalactic data sets. The sky boundaries ... -
A real time processing system for big data in astronomy: Applications to Hera
(Elsevier, 2021)As current- and next-generation astronomical instruments come online, they will generate an unprecedented deluge of data. Analyzing these data in real time presents unique conceptual and computational challenges, and their ... -
MIGHTEE-HI: discovery of an HI-rich galaxy group at z = 0.044 with MeerKAT
(Monthly Notices of the Royal Astronomical Society, 2021)We present the serendipitous discovery of a galaxy group in the XMM-LSS field with MIGHTEE Early Science observations. 20 galaxies are detected in HI in this z ∼ 0.044 group, with a 3σ column density sensitivity of NHI = ... -
Statistical recovery of the BAO scale from multipoles of the beam-convolved 21 cm correlation function
(Royal Astronomical Society, 2021)Despite being designed as an interferometer, theMeerKAT radio array (a Square Kilometre Array pathfinder) can also be used in autocorrelation (‘single-dish’) mode, where each dish scans the sky independently. Operating ... -
Reflectivity of VUV-sensitive silicon photomultipliers in liquid Xenon
(IOP Publishing, 2021)Silicon photomultipliers are regarded as a very promising technology for nextgeneration, cutting-edge detectors for low-background experiments in particle physics. This work presents systematic reflectivity studies of ... -
Null tests of the concordance model in the era of Euclid and the SKA
(Elsevier, 2021)We perform null tests of the concordance model, using H (z) measurements that mimic next-generation surveys such as Euclid and the SKA. To this end, we deploy a non-parametric method, so that we make minimal assumptions ... -
Pulsars with NenuFAR: Backend and pipelines
(EDP Sciences, 2021)Context. NenuFAR (New extension in Nançay upgrading LOFAR) is a new radio telescope developed and built on the site of the Nançay Radio Observatory. It is designed to observe the largely unexplored frequency window from ... -
The effect of finite halo size on the clustering of neutral hydrogen.
(IOP, 2021)Post-reionisation 21cm intensity mapping experiments target the spectral line of neutral hydrogen (HI) resident in dark matter haloes. According to the halo model, these discrete haloes trace the continuous dark matter ... -
Testing the equivalence principle on cosmological scales using the odd multipoles of galaxy cross-power spectrum and bispectrum
(IOP, 2021)One of the cornerstones of general relativity is the equivalence principle. However, the validity of the equivalence principle has only been established on solar system scales for standard matter fields; this result ... -
Synthesis, characterization and ab initio study of WO3 nanocubes with peculiar electrochemical properties
(Springer, 2021)Simple sol–gel method has been exploited to deposit Sn-doped TiO2 thin flms on glass substrates. The resultant coatings were characterized by X-ray difraction (XRD), UV–visible techniques (UV–Vis), Fourier transform ... -
Synthesis and characterization of Sn‑doped TiO2 flm for antibacterial applications
(Springer, 2021)Simple sol–gel method has been exploited to deposit Sn-doped TiO2 thin flms on glass substrates. The resultant coatings were characterized by X-ray difraction (XRD), UV–visible techniques (UV–Vis), Fourier transform ... -
Statistical gamma-ray decay studies at iThemba LABS
(EDP Sciences, 2017)Abstract. A program to study the γ -ray decay from the region of high-level density has been established at iThemba LABS, where a high-resolution gamma-ray detector array is used in conjunction with silicon particle-telescopes. ... -
Relativistic mean field formulation of clustering in heavy nuclei
(IOP, 2010)Very little is known about clustering in heavy nuclei and in particular the interaction between the correlated cluster nucleons and remaining core nucleons. Currently the phenomenological Saxon-Woods plus cubic Saxon-Woods ... -
Observation of the 0+ 2 and γ bands in 98Ru, and shape coexistence in the Ru isotopes
(Elsevier, 2020)Excited states in 98Ru were investigated using γ-ray spectroscopy following the β-decay of 98Rh, and via the 100Ru(p,t) reaction. Combining the results from the two experiments, two states were revised to have spin-parity ... -
Modern African nuclear detector laboratory: Development of state-of-the-art in-house detector facility at the University of the Western Cape
(SpringerLink, 2021)The upcoming detector facility aims at developing new state-of-the-art particle detectors as well as providing hands-on training to postgraduate students using both analog and digital signal processing from nuclear radiation ... -
Predicting coronary artery disease risk in firefighters – a cross-sectional study
(2021-07-30)Background: Firefighters are placed under severe cardiovascular load in performing active duty and, when carrying various coronary artery disease (CAD) risk factors, firefighters are predisposed to significant morbidity ...