Physics and Astronomy: Recent submissions
Now showing items 401-420 of 533
-
The baryonic Tully–Fisher relation in the SIMBA simulation
(Oxford University Press, 2020)We investigate the Baryonic Tully–Fisher relation (BTFR) in the (100h−1Mpc)3SIMBA hydrodynamical galaxy formation simulation together with a higher resolution (25h−1Mpc)3SIMBA run, for over 10 000 disc-dominated, H I-rich ... -
Unsupervised machine learning for transient discovery in deeper, wider, faster light curves
(Oxford University Press, 2020)Identification of anomalous light curves within time-domain surveys is often challenging. In addition, with the growing number of wide-field surveys and the volume of data produced exceeding astronomers’ ability for manual ... -
The evolution of the low-frequency radio AGN population to z 1.5 in the ELAIS N1 field
(Oxford University Press, 2021)We study the cosmic evolution of radio sources out to z ≃ 1.5 using a GMRT 610 MHz survey covering ∼1.86 deg2 of the ELAIS N1 field with a minimum/median rms noise 7.1/19.5 μJy beam−1 and an angular resolution of 6 arcsec. ... -
A LOFAR observation of ionospheric scintillation from two simultaneous travelling ionospheric disturbances
(The Journal of Space Weather and Space Climate, 2020)This paper presents the results from one of the first observations of ionospheric scintillation taken using the Low-Frequency Array (LOFAR). The observation was of the strong natural radio source Cassiopeia A, taken ... -
Recursion relations for gravitational lensing
(Springer Nature, 2019)The weak gravitational lensing formalism can be extended to the strong lensing regime by integrating a nonlinear version of the geodesic deviation equation. The resulting ‘roulette’ expansion generalises the notion of ... -
WALLABY – an SKA Pathfinder H I survey
(Springer Nature, 2020)The Widefield ASKAP L-band Legacy All-sky Blind surveY (WALLABY) is a next-generation survey of neutral hydrogen (H I) in the Local Universe. It uses the widefield, high-resolution capability of the Australian Square ... -
Model of compact star with ordinary and darkmatter
(Springer Nature, 2020)We study compact stars formed by dark and ordinary matter, with attributes of both neutron star matter and quark star matter. We assume an equation of state for dark matter which is consistent with the rotational ... -
An ALMA survey of the brightest sub-millimetre sources in the SCUBA-2–COSMOS field
(Oxford University Press, 2020)ABSTRACT We present an ALMA study of the ∼180 brightest sources in the SCUBA-2 850-μm map of the COSMOS field from the S2COSMOS survey, as a pilot study for AS2COSMOS – a full survey of the ∼1000 sources in this field. ... -
Possible periodic activity in the repeating FRB 121102
(Oxford University Press, 2020)The discovery that at least some Fast Radio Bursts (FRBs) repeat has ruled out cataclysmic events as the progenitors of these particular bursts. FRB 121102 is the most well-studied repeating FRB but despite extensive ... -
Lyman α absorption beyond the disc of simulated spiral galaxies
(Oxford University Press, 2020)We present an analysis of the origin and properties of the circumgalactic medium (CGM) in a suite of 11 cosmological zoom simulations resembling present-day spiral galaxies. On average the galaxies retain about 50 per cent ... -
Multipole expansion for H I intensity mapping experiments: simulations and modelling
(Oxford University Press, 2020)We present a framework and an open-source PYTHON toolkit to analyse the two-point statistics of 3D fluctuations in the context of H I intensity maps using the multipole expansion formalism. We include simulations of the ... -
The 2020 release of the ExoMol database: Molecular line lists for exoplanet and other hot atmospheres
(Elsevier, 2020)The ExoMol database (www.exomol.com) provides molecular data for spectroscopic studies of hot atmospheres. While the data are intended for studies of exoplanets and other astronomical bodies, the dataset is widely applicable. ... -
Global analysis of the COVID-19 pandemic using simple epidemiological models
(Elsevier, 2021)Several analytical models have been developed in this work to describe the evolution of fatalities arising from coronavirus COVID-19 worldwide. The Death or ‘D’ model is a simplified version of the well-known SIR ... -
Biomass Energy Dependence in South Africa: Are the Western Cape Province households descending the energy ladder after improvement in electricity access?
(Elsevier, 2020)South Africa was considered to have attained universal access to modern energy from 1994 to 2012. This meant that the number of households that moved away from the use of dirty energy to ... -
Controlled deposition of lead iodide and lead chloride thin films by low-pressure chemical vapor deposition
(MDPI, 2020)Lead halide thin films, such as lead iodide (PbI2) and lead chloride (PbCl2), are used as precursor films for perovskite preparation, which is frequently achieved by vacuum thermal evaporation but rarely by the low-pressure ... -
Synthesis and photovoltaics of novel 2,3,4,5-tetrathienylthiophene-co-poly(3-hexylthiophene-2,5-diyl) donor polymer for organic solar cell
(MPDI, 2021)This report focuses on the synthesis of novel 2,3,4,5-tetrathienylthiophene-co-poly(3-hexylthiophene-2,5-diyl) (TTT-co-P3HT) as a donor material for organic solar cells (OSCs). The properties of the synthesized TTT-co-P3HT ... -
Bio-synthesised black α-Cr2O3 nanoparticles; experimental analysis and density function theory calculations
(Elsevier, 2021)A selective single phase black α-Cr2O3 nanoparticles was bio-synthesised via simple straight-forward green synthesis approach. The process involves extraction of phytochemicals contained in peels of sweet potatoes. Extraction ... -
Electrochemical studies of Pd-based anode catalysts in alkaline medium for direct glycerol fuel cells
(MDPI, 2020)his study investigates the most effective electrocatalyst for glycerol oxidation reaction (GOR) in alkaline medium for five synthesized electrocatalysts, Pd, PdNi, PdNiO, PdMn3O4 and PdMn3O4NiO, supported on multi-walled ... -
Effects of alkali and transition metal-doped TiO2 hole blocking layers on the perovskite solar cells obtained by a two-step sequential deposition method in air and under vacuum
(Royal Society of Chemistry, 2020)Planar perovskite solar cells (PPSCs) have received great attention in recent years due to their intriguing properties, which make them a good choice for photovoltaic applications. In this work, the effect of alkali and ... -
Spin coating immobilisation of C-N-TiO2 Co-Doped nano catalyst on glass and application for photocatalysis or as electron transporting layer for perovskite solar cells
(MDPI, 2020)Producingactivethinfilmscoatedonsupportsresolvesmanyissuesofpowder-basedphoto catalysis and energy harvesting. In this study, thin films of C-N-TiO2 were prepared by dynamic spin coating of C-N-TiO2 sol-gel on glass support. ...