Browsing Research Articles (Physics) by Title
Now showing items 1-20 of 233
-
The 1.28 GHz MeerKAT DEEP2 Image
(2020)We present the confusion-limited 1.28 GHz MeerKAT DEEP2 image covering one qb » ¢ 68 FWHM primarybeam area with θ = 7 6 FWHM resolution and s = m - n 0.55 0.01 Jy beam 1 rms noise. Its J2000 center position α = 04h 13m ... -
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. ... -
Aligned metal absorbers and the ultraviolet background at the end of reionization
(Oxford University Press, 2018)We use observations of spatially-aligned C ii, C iv, Si ii, Si iv, and O i absorbers to probe the slope and intensity of the ultraviolet background (UVB) at z ∼ 6. We accom- plish this by comparing observations with ... -
All-sky angular power spectrum – I. Estimating brightness temperature fluctuations using the 150-MHz TGSS survey
(Oxford University Press, 2020)Measurements of the Galactic synchrotron emission are important for the 21-cm studies of the epoch of reionization. The study of synchrotron emission is also useful for quantifying the fluctuations in the magnetic field ... -
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. ... -
An ALMA survey of the SCUBA-2 CLS UDS field: Physical properties of 707 sub-millimetre galaxies
(Oxford University Press, 2020)We analyse the physical properties of a large, homogeneously selected sample of ALMA-located sub-millimetre galaxies (SMGs). This survey, AS2UDS, identified 707 SMGs across the ∼1 deg2 field, including ∼17 per cent, which ... -
Annealing effect of hybrid solar cells based on poly (3-hexylthiophene) and zinc-oxide nanostructures
(Elsevier, 2013)The structural growth and optical and photovoltaic properties of the organic–inorganic hybrid structures of zinc oxide (ZnO)-nanorods/poly-3-hexylthiophene (P3HT) and two variations of organic polymer blends of ZnO/ ... -
Anti-lensing: the bright side of voids
(American Physical Society, 2013)More than half of the volume of our Universe is occupied by cosmic voids. The lensing magni ca- tion e ect from those under-dense regions is generally thought to give a small dimming contribution: objects on the far side ... -
Assessing non-linear models for galaxy clustering – II. Model validation and forecasts for Stage IV surveys
(Oxford University Press, 2020)Accurate modelling of non-linear scales in galaxy clustering will be crucial for data analysis of Stage IV galaxy surveys. A selection of competing non-linear models must be made based on validation studies. We provide a ... -
Augmenting machine learning photometric redshifts with Gaussian mixture models
(Oxford University Press, 2020-09-11)Wide-area imaging surveys are one of the key ways of advancing our understanding of cosmology, galaxy formation physics, and the large-scale structure of the Universe in the coming years. These surveys typically require ... -
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 ... -
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 ... -
Black hole - galaxy correlations without self-regulation
(American Astronomical Society, 2013)Recent models of black hole growth in a cosmological context have forwarded a paradigm in which the growth is self-regulated by feedback from the black hole itself. Here we use cosmological zoom simulations of galaxy formation ... -
Bringing together knowledge and capabilities: a case study of engineering graduates
(Springer Verlag, 2016)In contemporary times there is a renewed focus on the purposes of university education in science or engineering, especially inemerging economycontexts like South Africa where the massification of higher education is in ... -
Broad-band radio polarimetry of disc galaxies and AGN with KAT-7
(Oxford University Press, 2020)We report broad-band (1.2–1.9 GHz) radio continuum observations at arcminute resolutions of two nearby disc galaxies, NGC 1808 and NGC 1097, and four active galactic nuclei (AGN)-powered radio sources: PKS B1934−638, PKS ... -
Calibrating photometric redshifts with intensity mapping observations
(American Physical Society, 2017)Imaging surveys of galaxies will have a high number density and angular resolution yet a poor redshift precision. Intensity maps of neutral hydrogen (HI) will have accurate redshift resolution yet will not resolve ... -
Calibrating the James Webb Space telescope filters as star formation rate indicators
(American Astronomical Society, 2018)We have calibrated the 6.5m James Webb Space Telescope (JWST) mid-infrared (MIR) filters as star formation rate (SFR) indicators, using JWST photometry synthesized from Spitzer spectra of 49 low-redshift galaxies, which ... -
A census of the pulsar population observed with the international LOFAR station FR606 at low frequencies (25–80 MHz)
(EDP Sciences, 2020)ontext. To date, only 69 pulsars have been identified with a detected pulsed radio emission below 100 MHz. A LOFAR-core LBA census and a dedicated campaign with the Nançay LOFAR station in stand-alone mode were carried out ... -
Characterization of silicon nitride thin films deposited by hot-wire CVD at low gas flow rates
(Elsevier, 2013)We examined the chemical, structural, mechanical and optical properties of amorphous hydrogenatedsilicon nitride thin films deposited by hot-wire chemical vapour deposition using SiH4, NH3and H2gases at total flow rates ... -
Classifying galaxies according to their H I content
(Oxford University Press, 2020)We use machine learning to classify galaxies according to their H I content, based on both their optical photometry and environmental properties. The data used for our analyses are the outputs in the range z = 0–1 from ...
