Research Articles (Physics): Recent submissions
Now showing items 121-140 of 520
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Multi-wavelength properties of radio- and machine-learning-identified counterparts to submillimeter sources in s2cosmos
(The Astrophysical Journal, 2019)We identify multi-wavelength counterparts to 1147 submillimeter sources from the S2COSMOS SCUBA-2 survey of the COSMOS field by employing a recently developed radio+machine-learning method trained on a large sample of ... -
An askap survey for hi absorption towards dust-obscured quasars
(Oxford Academic, 2019)Obscuration of quasars by accreted gas and dust, or dusty intervening galaxies, can cause active galactic nuclei (AGN) to be missed in optically selected surveys. Radio observations can overcome this dust bias. In particular, ... -
A highly responsive nh3 sensor based on pd-loaded zno nanoparticles prepared via a chemical precipitation approach
(ScienceDirect, 2019)The gas-detecting ability of nanostructured ZnO has led to significant attention being paid to the development of a unique and effective approach to its synthesis. However, its poor sensitivity, cross-sensitivity to humidity, ... -
A new sample of southern radio galaxies: Host-galaxy masses and star-formation rates
(Oxford University Press, 2019)In this study we define a new sample of distant powerful radio galaxies in order to study their host galaxy properties and provide targets for future observations of H I absorption with new radio telescopes and to understand ... -
A full treatment of peculiar velocities on the reionization light cone
(Oxford Academic, 2019)Accurate simulations of the 21-cm signal from the Epoch of Reionization require the generation of maps at specific frequencies given the values of astrophysical and cosmological parameters. The peculiar velocities of the ... -
Maximum sprite streamer luminosity near the stratopause
(AGU Advances, 2019)Sprites are composed of numerous streamers which exhibit transient luminosities in the upper middle atmosphere above thunderclouds after initiation by an intense positive lightning discharge, often followed by lightning ... -
Artist: Fast radiative transfer for large-scale simulations of the epoch of reionization
(Oxford University Press, 2019)We introduce the ‘Asymmetric Radiative Transfer In Shells Technique’ (ARTIST), a new method for photon propagation on large scales that explicitly conserves photons, propagates photons at the speed of light, approximately ... -
The observation of vibrating pear-shapes in radon nuclei
(nature communications, 2019)There is a large body of evidence that atomic nuclei can undergo octupole distortion and assume the shape of a pear. This phenomenon is important for measurements of electric-dipole moments of atoms, which would indicate ... -
Gravitational signal propagation in the double pulsar studied with the MeerKAT telescope
(Hans Publishers, 2022)The double pulsar PSR J0737−3039A/B has offered a wealth of gravitational experiments in the strong-field regime, all of which general relativity has passed with flying colours. In particular, among current gravity ... -
Nitrogen plasma treatment of zno and tio2 nanowire arrays for polymer photovoltaic applicationS
(ScienceDirect, 2019)This work reports on a simple, yet unique approach to improving the opto-electronic properties of vertically-aligned arrays of rutile TiO2 and Wurzite ZnO nanowires by means of controlled nitrogen doping during exposure ... -
Cold-pressing and vacuum arc melting of γ-tial based alloys
(ScienceDirect, 2019)eta (β) solidifying γ-TiAl intermetallic alloys of nominal composition Ti-48Al, Ti-48Al-2Nb, Ti-48Al-2Nb-0.7Cr alloys have been cold pressed and vacuum arc melted. The Al loss was due to compaction method used prior to the ... -
Comparing galaxy clustering in horizon-agn simulated light-cone mocks and video observations
(Oxford academic, 2019)Hydrodynamical cosmological simulations have recently made great advances in reproducing galaxy mass assembly over cosmic time – as often quantified from the comparison of their predicted stellar mass functions to observed ... -
Mergers, starbursts, and quenching in the SIMBA simulation
(Oxford Academic, 2019)We use the SIMBAcosmological galaxy formation simulation to investigate the relationship between major mergers (4:1), starbursts, and galaxy quenching. Mergers are identified via sudden jumps in stellar mass M∗ well above ... -
Comparing galaxy clustering in horizon-agn simulated light-cone mocks and video observations
(Oxford University Press, 2019-04-12)Hydrodynamical cosmological simulations have recently made great advances in reproducing galaxy mass assembly over cosmic time – as often quantified from the comparison of their predicted stellar mass functions to observed ... -
Astronomy for Development – A story from South Africa
(UWC, 2021)In this article we describe the recent history of astronomy in South Africa from the perspective of development. We describe how all major astronomy initiatives have carried a component of development with them, be it ... -
Inclusive education and research through African Network of Women in Astronomy and STEM for GIRLS in Ethiopia initiatives
(UWC, 2021)The African Network of Women in Astronomy and STEM for GIRLS in Ethiopia initiatives have been established with aim to strengthen the participation of girls and women in astronomy and science in Africa and Ethiopia. We ... -
Effect of the annealing atmosphere on the layer interdiffusion in Pd/Ti/Pd multilayer stacks deposited on pure Ti and Ti-alloy substrates
(University of the Western Cape, 2019)Pd(50 nm)/Ti(25 nm)/Pd(50 nm) multilayer stack has been deposited on Ti and Ti6Al4V substrates; we have studied the intermixing of layers upon annealing at the hydrogenation temperature of 550 °C, under vacuum, H/Ar gas ... -
Energy-momentum tensor and helicity for gauge fields coupled to a pseudoscalar inflaton
(University of the Western Cape, 2019)We study the energy-momentum tensor and helicity of gauge fields coupled through $g \phi F \tilde{F}/4$ to a pseudo-scalar field $\phi$ driving inflation. Under the assumption of a constant time derivative of the background ... -
Rotational structures in 196Hg
(University of the Western Cape, 2019)High spin states in 196 Hg were populated in the 198 Pt (α,6n) reaction at 65 MeV and γ −γ coincidence measurements were performed using the AFRODITE array at iThemba LABS. The level scheme was extended and new rotational ... -
On the primordial origin of the smoothing excess in the Planck temperature power spectrum in light of LSS data
(IOP Publishing, 2022)The Planck DR3 measurements of the temperature and polarization anisotropies power spectra of the cosmic microwave background (CMB) show an excess of smoothing of the acoustic peaks with respect to ΛCDM, often quantified ...