A5032994273- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Cosmology and Gravitation Theories
- Dark Matter and Cosmic Phenomena
- Scientific Research and Discoveries
- Astrophysics and Star Formation Studies
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Radio Astronomy Observations and Technology
- Astronomical Observations and Instrumentation
- Adaptive optics and wavefront sensing
- Astrophysical Phenomena and Observations
- History and Developments in Astronomy
- CCD and CMOS Imaging Sensors
- Geophysics and Gravity Measurements
- Solar and Space Plasma Dynamics
- Computational Physics and Python Applications
- Plant Water Relations and Carbon Dynamics
- Remote Sensing in Agriculture
- Neutrino Physics Research
- Relativity and Gravitational Theory
- Particle physics theoretical and experimental studies
- Pulsars and Gravitational Waves Research
- Space Science and Extraterrestrial Life
Durham University
2016-2025
Indiana Cancer Consortium
2005-2025
University of North Carolina at Chapel Hill
2018-2024
Kansas State University
2024
University College Lahore
2023
Durham Technical Community College
1997-2021
Friedrich-Alexander-Universität Erlangen-Nürnberg
2021
Universitätsklinikum Erlangen
2021
CNR de la Résistance aux Antibiotiques
2021
Agence française de développement
2018
We use high-resolution N-body simulations to study the equilibrium density profiles of dark matter halos in hierarchically clustering universes. find that all such have same shape, independent halo mass, initial fluctuation spectrum, and values cosmological parameters. Spherically averaged are well fitted over two decades radius by a simple formula originally proposed describe structure galaxy clusters cold universe. In any particular cosmology, scale parameters fit, mass its characteristic...
view Abstract Citations (6847) References (69) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Structure of Cold Dark Matter Halos Navarro, Julio F. ; Frenk, Carlos S. White, Simon D. M. We use N-body simulations to investigate the structure dark halos in standard cold matter cosmogony. are excised from cosmologically representative regions and resimulated individually at high resolution. study objects with masses ranging those dwarf galaxy rich clusters....
We introduce the Virgo Consortium's EAGLE project, a suite of hydrodynamical simulations that follow formation galaxies and black holes in representative volumes. discuss limitations such light their finite resolution poorly constrained subgrid physics, how these affect predictive power. One major improvement is our treatment feedback from massive stars AGN which thermal energy injected into gas without need to turn off cooling or forces, allowing winds develop predetermined speed mass...
view Abstract Citations (3074) References (60) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The evolution of large-scale structure in a universe dominated by cold dark matter Davis, M. ; Efstathiou, G. Frenk, C. S. White, D. results numerical simulations nonlinear gravitational clustering universes weakly interacting, 'cold' are presented. methods used and the way which initial conditions were generated described, performed catalogued. fundamental...
Recent observations of the distant Universe suggest that much stellar mass bright galaxies was already in place at z > 1. This presents a challenge for models galaxy formation because massive haloes are assembled late hierarchical clustering process intrinsic to cold dark matter (CDM) cosmology. In this paper, we discuss new implementation Durham semi-analytic model which feedback due active galactic nuclei (AGN) is assumed quench cooling flows haloes. mechanism naturally creates break local...
The 2dF Galaxy Redshift Survey (2dFGRS) is designed to measure redshifts for approximately 250-000 galaxies. This paper describes the survey design, spectroscopic observations, redshift measurements and data base. 2dFGRS uses multifibre spectrograph on Anglo-Australian Telescope, which capable of observing 400 objects simultaneously over a 2° diameter field. source catalogue revised extended version APM galaxy catalogue, targets are galaxies with extinction-corrected magnitudes brighter than...
view Abstract Citations (2043) References (142) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Galaxy Formation through Hierarchical Clustering White, Simon D. M. ; Frenk, Carlos S. We develop analytic methods for studying the formation of galaxies by gas condensation within massive dark halos. Our scheme applies to cosmogonies where structure grows hierarchical clustering a mixture and dissipationless matter. It is an elaboration ideas White & Rees. adopt...
We present a power-spectrum analysis of the final 2dF Galaxy Redshift Survey (2dFGRS), employing direct Fourier method. The sample used comprises 221 414 galaxies with measured redshifts. investigate in detail modelling selection, improving on previous treatments number respects. A new angular mask is derived, based revisions to photometric calibration. redshift selection function determined by dividing survey according rest-frame colour, and deducing self-consistent treatment k-corrections...
We present the results of a large library cosmological N-body simulations, using power-law initial spectra. The nonlinear evolution matter power spectra is compared with predictions existing analytic scaling formulae based on work Hamilton et al. approach has assumed that highly structures obey `stable clustering' and are frozen in proper coordinates. Our show that, when transformed under self-similarity scaling, scale-free define locus clearly shallower than would be required stable...
We simulate the growth of galaxies and their central supermassive black holes by implementing a suite semi-analytic models on output Millennium Run, very large simulation concordance Λ cold dark matter cosmogony. Our procedures follow detailed assembly history each object are able to track evolution all more massive than Small Magellanic Cloud throughout volume comparable that modern redshift surveys. In this first paper we supplement previous treatments activity with new model for 'radio'...
We describe the GALFORM semi-analytic model for calculating formation and evolution of galaxies in hierarchical clustering cosmologies. It improves upon, extends, earlier scheme developed by Cole et al. The employs a new Monte Carlo algorithm to follow merging dark matter haloes with arbitrary mass resolution. incorporates realistic descriptions density profiles gas they contain; it follows chemical stars, associated production dust; includes detailed calculation sizes discs spheroids....
We have performed the largest ever particle simulation of a Milky Way-sized dark matter halo, and present most comprehensive convergence study for an individual halo carried out thus far. also simulated sample 6 ultra-highly resolved Milky-way sized halos, allowing us to estimate halo-to-halo scatter in substructure statistics. In our simulation, we resolve nearly 300,000 gravitationally bound subhalos within virialized region halo. Simulations same object differing mass resolution by...
We combine data from a number of N-body simulations to predict the abundance dark haloes in cold matter (CDM) universes over more than four orders magnitude mass. A comparison different suggests that dominant uncertainty our results is systematic and smaller 10–30 per cent at all masses, depending on halo definition used. In particular, 'Hubble volume' τCDM ΛCDM cosmologies allow massive clusters be predicted with uncertainties well below those expected currently planned observational...
DESI (Dark Energy Spectroscopic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations (BAO) and the growth of structure through redshift-space distortions with wide-area galaxy quasar redshift survey. To trace underlying matter distribution, spectroscopic targets be selected in four classes from imaging data. We measure luminous red galaxies up to $z=1.0$. probe Universe out even higher redshift, target bright [O II] emission line $z=1.7$....
We present results from thirteen cosmological simulations that explore the parameter space of "Evolution and Assembly GaLaxies their Environments" (EAGLE) simulation project. Four follow evolution a periodic cube L = 50 cMpc on side, each employs different subgrid model energetic feedback associated with star formation. The relevant parameters were adjusted so reproduce observed galaxy stellar mass function at z 0.1. Three fail to form disc galaxies as extended observed, we show analytically...
Pan-STARRS1 has carried out a set of distinct synoptic imaging sky surveys including the $3π$ Steradian Survey and Medium Deep in 5 bands ($grizy_{P1}$). The mean 5$σ$ point source limiting sensitivities stacked 3$π$ $grizy_{P1}$ are (23.3, 23.2, 23.1, 22.3, 21.4) respectively. upper bound on systematic uncertainty photometric calibration across is 7-12 millimag depending bandpass. astrometric using Gaia frame comes from comparison results with Gaia: standard deviation median residuals ($...
The population of rich galaxy clusters evolves much more rapidly in a universe with critical density than low density. Thus, counts at intermediate redshift offer the possibility determining cosmological parameter, Ω0, minimum assumptions. We quantify this evolution using Press-Schechter formalism which we extend to flat models constant, Λ0 = 1 − Ω0 Using new large N-body simulations, verify that accurately predicts abundance as function various cosmologies. normalize by comparing them local...
We investigate the mass profile of LambdaCDM halos using a suite numerical simulations spanning five decades in halo mass, from dwarf galaxies to rich galaxy clusters. Our analysis confirms proposal Navarro, Frenk & White (NFW) that shape profiles differs strongly power law and depends little on mass. The logarithmic slope spherically-averaged density profile, as measured by beta=-dln(rho)/dln(r), decreases monotonically towards center becomes shallower than isothermal (beta<2) inside...
We present simulations of the formation and evolution galaxy clusters in Cold Dark Matter cosmogony. Clusters with a wide range mass were selected from previous N-body models, resimulated at higher resolution using combined N-body/Smooth Particle Hydrodynamics code. The effects radiative cooling on gas are neglected. While many present-day predicted to be undergoing mergers, density profiles those that approximately equilibrium all very similar, both for dark matter. These show no sign...
The Galaxy And Mass Assembly (GAMA) survey has been operating since February 2008 on the 3.9-m Anglo-Australian Telescope using AAOmega fibre-fed spectrograph facility to acquire spectra with a resolution of R~1300 for 120,862 SDSS selected galaxies. target catalogue constitutes three contiguous equatorial regions centred at 9h (G09), 12h (G12) and 14.5h (G15) each 12 x 4 sq.deg limiting fluxes r < 19.4, 19.8, 19.4 mag respectively (and additional limits other wavelengths). Spectra reliable...
We present a comprehensive set of convergence tests which explore the role various numerical parameters on equilibrium structure simulated dark matter halo. report results obtained with two independent, state-of-the-art, multi-stepping, parallel N-body codes: pkdgrav and gadget. find that convergent mass profiles can be for suitable choices gravitational softening, time-step, force accuracy, initial redshift, particle number. For softenings chosen so discreteness effects are negligible, in...
We combine the Two Micron All Sky Survey (2MASS) Extended Source Catalogue and 2dF Galaxy Redshift to produce an infrared selected galaxy catalogue with 17 173 measured redshifts. use this extensive data set estimate luminosity functions in J- KS-bands. The are fairly well fitted by Schechter parameters MJ*−5 log h = −22.36±0.02, αJ −0.93±0.04, ΦJ* 0.0104±0.0016 h3 Mpc−3 J-band MKS*−5 −23.44±0.03, αKS −0.96±0.05, ΦKS* 0.0108±0.0016 KS-band (2MASS Kron magnitudes). These derived assuming a...