Browsing Research Articles (Physics) by Title
Now showing items 211-230 of 510
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HI intensity mapping with the MIGHTEE survey: power spectrum estimates
(Monthly Notices of the Royal Astronomical Society, 2021)Intensity mapping (IM) with neutral hydrogen is a promising avenue to probe the large scale structure of the Universe. In this paper, we demonstrate that using the 64-dish MeerKAT radio telescope as a connected interferometer, ... -
Hierarchiral 4-tetranitro copper(II)phthalocyanine based metal organic framework hybrid composite with improved electrocatalytic efficiency towards hydrogen evolution reaction
(Elsivier, 2019)A novel hybrid-hybrid nanocomposite based on 4-tetranitro copper(II)phthalocyanine (TNCuPc) grown on metal organic frameworks (MOF) as a noble metal-free catalyst for hydrogen evolution reaction (HER) was developed by a ... -
Hiflow: Generating diverse hi maps and inferring cosmology while marginalizing over astrophysics using normalizing flows
(IOP Publishing, 2022)A wealth of cosmological and astrophysical information is expected from many ongoing and upcoming large-scale surveys. It is crucial to prepare for these surveys now and develop tools that can efficiently extract ... -
High Molecular-gas to Dust Mass Ratios Predicted in Most Quiescent Galaxies
(American Astronomical Society, 2021)Observations of cold molecular gas reservoirs are critical for understanding the shutdown of star formation in massive galaxies. While dust continuum is an efficient and affordable tracer, this method relies upon the ... -
The high-ion content and kinematics of low-redshift lyman limit systems
(The American Astronomical Society, 2013)We study the high-ion content and kinematics of the circumgalactic medium around low-redshift galaxies using a sample of 23 Lyman limit systems (LLSs) at 0.08 < z < 0.93 observed with the Cosmic Origins Spectrograph on ... -
High-Precision Branching Ratio Measurement for the Superallowed + Emitter 74Rb
(American Physical Society, 2013)A high-precision branching-ratio measurement for the superallowed β + decay of 74Rb was performed at the TRIUMF Isotope Separator and Accelerator (ISAC) radioactive ion-beam facility. The scintillating electronpositron tagging ... -
High-precision half-life determination of 14O via direct β counting
(Springer, 2022)The half-life of the superallowed Fermi β+ emitter 14O was determined to high precision via a direct β counting experiment performed at the Isotope Separator and Accelerator (ISAC) facility at TRIUMF. The result, T1/2( 14O) ... -
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, ... -
The host haloes of O I absorbers in the reionization epoch
(Oxford University Press, 2013)We use a radiation hydrodynamic simulation of the hydrogen reionization epoch to study OI absorbers at z ∼ 6. The intergalactic medium (IGM) is reionized before it is enriched; hence, OI absorption originates within dark ... -
Hot subdwarf stars in close-up view IV. Helium abundances and the 3He isotopic anomaly of subdwarf B stars
(EDP Sciences, 2013)Atmospheric parameters and helium abundances of 44 bright subdwarf B stars have been determined. More than half of our sample consists of newly discovered stars from the Edinburgh Cape survey. We showed that effective ... -
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 ... -
How open data and interdisciplinary collaboration improve our understanding of space weather: A risk and resiliency perspective
(Frontiers Media, 2022)Space weather refers to conditions around a star, like our Sun, and its interplanetary space that may affect space- and ground-based assets as well as human life. Space weather can manifest as many different phenomena, often ... -
How well can we measure the stellar mass of a galaxy: The impact of the assumed star formation history model in SED fitting
(IOP Publishing, 2020)The primary method for inferring the stellar mass (M∗) of a galaxy is through spectral energy distribution (SED) modeling. However, the technique rests on assumptions such as the galaxy star formation history and dust ... -
The Hubble constant tension with next-generation galaxy surveys
(IOP Publishing Ltd, 2020)The rate at which the universe is expanding today is a fundamental parameter in cosmology which governs our understanding of structure formation and dark energy. However, current measurements of the Hubble constant, H0, ... -
Hunting down horizon-scale effects with multi-wavelength surveys
(American Astronomical Society, 2015)Next-generation cosmological surveys will probe ever larger volumes of the universe, including the largest scales, near and beyond the horizon. On these scales, the galaxy power spectrum carries signatures of local primordial ... -
Hybrid P` (k): General, unified, non-linear matter power spectrum in redshift space
(IOP Publishing Ltd, 2020)Constraints on gravity and cosmology will greatly benefit from performing joint clustering and weak lensing analyses on large-scale structure data sets. Utilising non-linear information coming from small physical scales ... -
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) ... -
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 ... -
Identification of single spectral lines in large spectroscopic surveys using UMLAUT: an Unsupervised Machine Learning Algorithm based on Unbiased Topology
(The Astrophysical Journal Supplement Series, 2021)The identification of an emission line is unambiguous when multiple spectral features are clearly visible in the same spectrum.However, in many cases, only one line is detected, making it difficult to correctly determine ... -
Identifying multiple periodicities in sparse photon event time series
(Oxford University Press, 2016)The data considered are event times (e.g. photon arrival times, or the occurrence of sharp pulses). The source is multiperiodic, or the data could be multiperiodic because several unresolved sources contribute to the time ...