Physics and Astronomy: Recent submissions
Now showing items 321-340 of 520
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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 ... -
Measurement and analysis of nuclear γ-ray production cross sections in proton interactions with Mg, Si, and Fe nuclei abundant in astrophysical sites over the incident energy range E = 30–66 MeV
(American Physical Society, 2020)The modeling of nuclear γ -ray line emission induced by highly accelerated particles in astrophysical sites (e.g., solar flares, the gas and dust in the inner galaxy) and the comparison with observed emissions from these ... -
J1615+5452: a remnant radio galaxy in the ELAIS-N1 field
(Oxford University Press, 2020)We report the discovery of a remnant radio active galactic nucleus (AGN) J1615+5452 in the field of ELAIS-N1. GMRT continuum observations at 150, 325, and 610 MHz combined with archival data from the 1.4 GHz NVSS survey ... -
K-CLASH: spatially resolving star-forming galaxies in field and cluster environments at z ≈ 0.2–0.6
(Oxford University Press, 2020)We present the KMOS-CLASH (K-CLASH) survey, a K-band Multi-Object Spectrograph (KMOS) survey, of the spatially resolved gas properties and kinematics of 191 (pre-dominantly blue) H α-detected galaxies at 0.2 ≲ z ≲ 0.6 in ... -
Foreground modelling via Gaussian process regression: an application to HERA data
(Oxford University Press, 2020)The key challenge in the observation of the redshifted 21-cm signal from cosmic reionization is its separation from the much brighter foreground emission. Such separation relies on the different spectral properties of the ... -
Deep GMRT 610 MHz observations of the ELAIS N1 field: Catalogue and source counts
(Oxford University Press, 2019)This is the first of a series of papers based on sensitive 610 MHz observations of the ELAIS N1 field, using the Giant Metrewave Radio Telescope. We describe the observations, processing and source catalogue extraction ... -
Extracting the global signal from 21-cm fluctuations: the multitracer approach
(Oxford University Press, 2019)The multitracer technique employs a ratio of densities of two differently biased galaxy samples that trace the same underlying matter density field, and was proposed to alleviate the cosmic variance problem. Here, we propose ... -
NIFTY galaxy cluster simulations – VI. The dynamical imprint of substructure on gaseous cluster outskirts
(Oxford University Press, 2019)Galaxy cluster outskirts mark the transition region from the mildly non-linear cosmic web to the highly non-linear, virialized, cluster interior. It is in this transition region that the intracluster medium (ICM) begins ... -
Detection of Cross-Correlation between Gravitational Lensing and γ Rays
(American Physical Society, 2020)In recent years, many γ -ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of ... -
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 ... -
Non-Gaussianity constraints using future radio continuum surveys and the multitracer technique
(Oxford University Press, 2019)Tighter constraints on measurements of primordial non-Gaussianity (PNG) will allow the differentiation of inflationary scenarios. The cosmic microwave background bispectrum – the standard method of measuring the local ... -
The frequency of very young galaxies in the local Universe – II. The view from SDSS spectra
(Oxford University Press, 2019)Only a handful of galaxies in the local Universe appear to be very young. We estimate the fraction of very young galaxies (VYGs), defined as those with more than half their stellar masses formed within the last Gyr. We fit ... -
Galaxy And Mass Assembly (GAMA): Defining passive galaxy samples and searching for the UV upturn
(Oxford University Press, 2019)We use data from the GAMA and GALEX surveys to demonstrate that the UV upturn, an unexpected excess of ultraviolet flux from a hot stellar component, seen in the spectra of many early-type galaxies, arises from processes ... -
Testing galaxy formation simulations with damped Lyman-α abundance and metallicity evolution
(Oxford University Press, 2020)We examine the properties of damped Lyman-α absorbers (DLAs) emerging from a single set of cosmological initial conditions in two state-of-the-art cosmological hydrodynamic simulations: SIMBA and TECHNICOLOR DAWN. The ... -
A null test to probe the scale dependence of the growth of structure as a test of general relativity
(Oxford University Press, 2019)The main science driver for the coming generation of cosmological surveys is understanding dark energy that relies on testing general relativity on the largest scales. Once we move beyond the simplest explanation for dark ... -
The impact of the connectivity of the cosmic web on the physical properties of galaxies at its nodes
(Oxford University Press, 2019)We investigate the impact of the number of filaments connected to the nodes of the cosmic web on the physical properties of their galaxies using the Sloan Digital Sky Survey. We compare these measurements to the cosmological ... -
Developing a unified pipeline for large-scale structure data analysis with angular power spectra – II. A case study for magnification bias and radio continuum surveys
(Oxford University Press, 2019)Following on our purpose of developing a unified pipeline for large-scale structure data analysis with angular power spectra, we now include the weak lensing effect of magnification bias on galaxy clustering in a publicly ... -
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: ... -
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 ... -
The impact of wind scalings on stellar growth and the baryon cycle in cosmological simulations
(Oxford University Press, 2020)Many phenomenologically successful cosmological simulations employ kinetic winds to model galactic outflows. Yet systematic studies of how variations in kinetic wind scalings might alter observable galaxy properties are ...