Browsing Research Articles (Physics) by Title
Now showing items 76-95 of 510
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Constraints on anisotropic cosmic expansion from supernovae
(Edp Sciences, 2013)AIMS. We test the isotropy of the expansion of the Universe by estimating the hemispherical anisotropy of supernova type Ia (SN Ia) Hubble diagrams at low redshifts (z < 0.2). METHODS. We compare the best fit Hubble ... -
Continuing influence of shell effects at high-excitation energies
(Elsevier, 2019)Empirical drops in ground-state nuclear polarizabilities indicate deviations from the effect of giant dipole resonances and may reveal the presence of shell effects in semi-magic nuclei with neutron magic numbers N = 50, ... -
The contribution of discrete sources to the sky temperature at 144 MHz
(EDP Sciences, 2021)In recent years, the level of the extragalactic radio background has become a point of considerable interest, with some lines of argument pointing to an entirely new cosmological synchrotron background. The contribution ... -
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 ... -
The Copernican principle in light of the latest cosmological data
(University of the Western Cape, 2022)We pursue a program to confront observations with inhomogeneous extensions of the FLRW metric. The main idea is to test the Copernican principle (CP) rather than assuming it a priori. We consider the CDM model endowed with ... -
Corrosion improvement of 304l stainless steel by zrsin and zrsi(N,o) mono-and double-layers prepared by reactive cathodic arc evaporation
(MDPI, 2021)Zr-based nitrides and oxynitrides were deposited by reactive cathodic arc evaporation in monolayer and double-layer structures with the aim of increasing the corrosion protection of 304L stainless steel (SS) in a biomedical ... -
The COS-Halos survey: Rationale, design and a census of circumgalactic neutral hydrogen
(IOP Publishing, 2013)We present the design and methods of the COS-Halos survey, a systematic investigation of the gaseous halos of 44 z = 0.15–0.35 galaxies using background QSOs observed with the Cosmic Origins Spectrograph aboard the Hubble ... -
Cosmic evolution of star-forming galaxies to z 1.8 in the faint low-frequency radio source population
(Oxford University Press, 2019)We study the properties of star-forming galaxies selected at 610 MHz with the GMRT in a survey covering ∼1.86 deg2 down to a noise of ∼7.1 μJy beam−1. These were identified by combining multiple classification diagnostics: ... -
The cosmic evolution of the IMF under the Jeans conjecture with implications for massive galaxies
(Oxford University Press, 2013)We examine the cosmic evolution of a stellar initial mass function (IMF) in galaxies that varies with the Jeans mass in the interstellar medium, paying particular attention to the K-band stellar mass-to-light ratio (M/LK) ... -
Cosmic microwave background constraints on a physical model of reionization
(Oxford University Press, 2021)We study constraints on allowed reionization histories by comparing predictions of a physical seminumerical model with secondary temperature and polarization anisotropies of the cosmic microwave background (CMB). Our model ... -
Cosmic sands: the origin of dusty, star-forming galaxies in the epoch of reionization
(The astrophysical journal, 2023)We present the Cosmic Sands suite of cosmological zoom-in simulations based on the simba galaxy formation model in order to study the buildup of the first massive and dusty galaxies in the early universe. Residing in the ... -
Cosmological 3D Hi Gas Map with HETDEX Lyα Emitters and eBOSS QSOs at z = 2: IGM-Galaxy/QSO Connection and a ∼ 40-Mpc Scale Giant Hii Bubble Candidate
(IOP Publishing, 2020)We present cosmological (30−400 Mpc) distributions of neutral hydrogen (H i) in the intergalactic medium (IGM) traced by Lyα emitters (LAEs) and QSOs at z = 2.1–2.5, selected with the data of the ongoing Hobby–Eberly ... -
Cosmological baryon transfer in the SIMBA simulations
(Oxford University Press, 2019)We present a framework for characterizing the large-scale movement of baryons relative to dark matter in cosmological simulations, requiring only the initial conditions and final state of the simulation. This is performed ... -
Cosmological constraints from the power spectrum and bispectrum of 21cm intensity maps
(IOP Publishing, 2022)The 21cm emission of neutral hydrogen is a potential probe of the matter distribution in the Universe after reionisation. Cosmological surveys of this line intensity will be conducted in the coming years by the SKAO and ... -
Cosmological constraints on post-Newtonian parameters in effectively massless scalar-tensor theories of gravity
(2019)We study the cosmological constraints on the variation of Newton’s constant and on post-Newtonian parameters for simple models of the scalar-tensor theory of gravity beyond the extended Jordan-BransDicke theory. We restrict ... -
Cosmology on ultralarge scales with intensity mapping of the neutral hydrogen 21 cm emission: limits on primodial non-gaussianity
(American Physical Society, 2013)The large-scale structure of the Universe supplies crucial information about the physical processes at play at early times. Unresolved maps of the intensity of 21 cm emission from neutral hydrogen HI at redshifts z ~ 1 − ... -
Cosmology with Phase 1 of the Square Kilometre Array Red Book 2018: Technical specifications and performance forecasts
(Cambridge University Press, 2020)We present a detailed overview of the cosmological surveys that we aim to carry out with Phase 1 of the Square Kilometre Array (SKA1) and the science that they will enable. We highlight three main surveys: a medium-deep ... -
Cosmology with photometrically classified type IA supernovae from the SDSS-II supernova survey
(The American Astronomical Society, 2013)We present the cosmological analysis of 752 photometrically–classified Type Ia Supernovae (SNe Ia) obtained from the full Sloan Digital Sky Survey II (SDSS-II) Supernova (SN) Survey, supplemented with host–galaxy ... -
COSMOS2020: A panchromatic view of the universe to z ∼ 10 from two complementary catalogs
(University of the Western Cape, 2022)The Cosmic Evolution Survey (COSMOS) has become a cornerstone of extragalactic astronomy. Since the last public catalog in 2015, a wealth of new imaging and spectroscopic data have been collected in the COSMOS field. This ... -
Cosmos2020: A panchromatic view of the universe to z∼10 from two complementary catalogs
(IOP Publishing, 2022)The Cosmic Evolution Survey (COSMOS) has become a cornerstone of extragalactic astronomy. Since the last public catalog in 2015, a wealth of new imaging and spectroscopic data have been collected in the COSMOS field. This ...