Institution
University of Portsmouth
Education•Portsmouth, Portsmouth, United Kingdom•
About: University of Portsmouth is a education organization based out in Portsmouth, Portsmouth, United Kingdom. It is known for research contribution in the topics: Population & Galaxy. The organization has 5452 authors who have published 14256 publications receiving 424346 citations. The organization is also known as: Portsmouth and Gosport School of Science and Art & Portsmouth and Gosport School of Science and the Arts.
Topics: Population, Galaxy, Redshift, Context (language use), Computer science
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the authors investigated how the [O II] properties and the morphologies of galaxies in clusters and groups at z = 0.4 − 0.8 depend on projected local galaxy density, and compare with the field at similar redshifts and clusters at low z.
Abstract: We investigate how the [O II] properties and the morphologies of galaxies in clusters and groups at z = 0.4–0.8 depend on projected local galaxy density, and compare with the field at similar redshifts and clusters at low z. In both nearby and distant clusters, higher density regions contain proportionally fewer star-forming galaxies, and the average [O II] equivalent width of star-forming galaxies is independent of local density. However, in distant clusters the average current star formation rate (SFR) in star-forming galaxies seems to peak at densities ~15-40 galaxies Mpc^−2. At odds with low-z results, at high z the relation between star-forming fraction and local density varies from high- to low-mass clusters. Overall, our results suggest that at high z the current star formation (SF) activity in star-forming galaxies does not depend strongly on global or local environment, though the possible SFR peak seems at odds with this conclusion. We find that the cluster SFR normalized by cluster mass anticorrelates with mass and correlates with the star-forming fraction. These trends can be understood given (1) that the average star-forming galaxy forms about 1⊙M yr^−1 (uncorrected for dust) in all clusters; (2) that the total number of galaxies scales with cluster mass; and (3) the dependence of star-forming fraction on cluster mass. We present the morphology-density (MD) relation for our z = 0.4 − 0.8 clusters, and uncover that the decline of the spiral fraction with density is entirely driven by galaxies of type Sc or later. For galaxies of a given Hubble type, we see no evidence that SF properties depend on local environment. In contrast with recent findings at low z, in our distant clusters the SF-density relation and the MD relation are equivalent, suggesting that neither of the two is more fundamental than the other.
182 citations
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TL;DR: The findings suggest a new picture in which brightest cluster galaxies experience an early period of rapid growth rather than prolonged hierarchical assembly, which conflict with the most recent galaxy formation models based on the largest simulations of dark-matter halo development.
Abstract: The current consensus is that galaxies begin as small density fluctuations in the early Universe and grow by in situ star formation and hierarchical merging. Stars begin to form relatively quickly in sub-galactic-sized building blocks called haloes which are subsequently assembled into galaxies. However, exactly when this assembly takes place is a matter of some debate. Here we report that the stellar masses of brightest cluster galaxies, which are the most luminous objects emitting stellar light, some 9 billion years ago are not significantly different from their stellar masses today. Brightest cluster galaxies are almost fully assembled 4-5 billion years after the Big Bang, having grown to more than 90 per cent of their final stellar mass by this time. Our data conflict with the most recent galaxy formation models based on the largest simulations of dark-matter halo development. These models predict protracted formation of brightest cluster galaxies over a Hubble time, with only 22 per cent of the stellar mass assembled at the epoch probed by our sample. Our findings suggest a new picture in which brightest cluster galaxies experience an early period of rapid growth rather than prolonged hierarchical assembly.
181 citations
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University of Leicester1, British Geological Survey2, American Museum of Natural History3, University of Cambridge4, Open University5, University College London6, University of Hull7, University of Portsmouth8, The Hertz Corporation9, Lancaster University10, Cardiff University11, National Oceanography Centre12, BG Group13
TL;DR: The Anthropocene, an informal term used to signal the impact of collective human activity on biological, physical and chemical processes on the Earth system, is assessed using stratigraphic criteria and includes geologically novel aspects and geologically will have permanent effects.
Abstract: The Anthropocene, an informal term used to signal the impact of collective human activity on biological, physical and chemical processes on the Earth system, is assessed using stratigraphic criteria. It is complex in time, space and process, and may be considered in terms of the scale, relative timing, duration and novelty of its various phenomena. The lithostratigraphic signal includes both direct components, such as urban constructions and man-made deposits, and indirect ones, such as sediment flux changes. Already widespread, these are producing a significant ‘event layer’, locally with considerable long-term preservation potential. Chemostratigraphic signals include new organic compounds, but are likely to be dominated by the effects of CO2 release, particularly via acidification in the marine realm, and man-made radionuclides. The sequence stratigraphic signal is negligible to date, but may become geologically significant over centennial/millennial time scales. The rapidly growing biostratigraphic signal includes geologically novel aspects (the scale of globally transferred species) and geologically will have permanent effects.
181 citations
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California Institute of Technology1, ASTRON2, University of Sussex3, University of Hertfordshire4, University of Portsmouth5, University of the Western Cape6, University of Padua7, University of California, Davis8, University of Cambridge9, University of Lisbon10, University of California, Riverside11, McGill University12, Commonwealth Scientific and Industrial Research Organisation13, Drexel University14, Lawrence Livermore National Laboratory15, Durham University16, Spanish National Research Council17, University of Oxford18, Imperial College London19, Istituto Nazionale di Fisica Nucleare20, University of Naples Federico II21, Space Telescope Science Institute22, University of Nottingham23, University of Hawaii24, University of Calgary25, Max Planck Society26, University of Edinburgh27, University of Wisconsin-Madison28, Carnegie Institution for Science29, Commissariat à l'énergie atomique et aux énergies alternatives30, Leiden University31, Haverford College32, Liverpool John Moores University33, Leibniz Association34
TL;DR: The Spitzer Extragalactic Representative Volume Survey (SERVS) as discussed by the authors is designed to enable the study of galaxy evolution as a function of environment from z~5 to the present day, and is the first survey both large enough and deep enough to put rare objects such as luminous quasars and galaxy clusters at z>1 into their cosmological context.
Abstract: We present the Spitzer Extragalactic Representative Volume Survey (SERVS), an 18 square degrees medium-deep survey at 3.6 and 4.5 microns with the post-cryogenic Spitzer Space Telescope to ~2 microJy (AB=23.1) depth of five highly observed astronomical fields (ELAIS-N1, ELAIS-S1, Lockman Hole, Chandra Deep Field South and XMM-LSS). SERVS is designed to enable the study of galaxy evolution as a function of environment from z~5 to the present day, and is the first extragalactic survey both large enough and deep enough to put rare objects such as luminous quasars and galaxy clusters at z>1 into their cosmological context. SERVS is designed to overlap with several key surveys at optical, near- through far-infrared, submillimeter and radio wavelengths to provide an unprecedented view of the formation and evolution of massive galaxies. In this paper, we discuss the SERVS survey design, the data processing flow from image reduction and mosaicing to catalogs, as well as coverage of ancillary data from other surveys in the SERVS fields. We also highlight a variety of early science results from the survey.
181 citations
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University of Portsmouth1, Lawrence Berkeley National Laboratory2, Yale University3, South East Physics Network4, University of Wyoming5, University of California, Berkeley6, Max Planck Society7, New York University8, Apache Corporation9, Case Western Reserve University10, Spanish National Research Council11, Harvard University12, Pennsylvania State University13, University of Arizona14
TL;DR: In this paper, the effects of potential sources of systematic error on the angular and photometric redshift, zphot, distributions of a sample of redshift 0.4 0.5, the magnitude of the corrections they apply is greater than the statistical uncertainty in w(θ).
Abstract: We investigate the effects of potential sources of systematic error on the angular and photometric redshift, zphot, distributions of a sample of redshift 0.4 0.5, the magnitude of the corrections we apply is greater than the statistical uncertainty in w(θ). The photometric redshift catalogue we produce will be made publicly available at http://portal.nersc.gov/project/boss/galaxy/photoz/.
181 citations
Authors
Showing all 5624 results
Name | H-index | Papers | Citations |
---|---|---|---|
Robert C. Nichol | 187 | 851 | 162994 |
Gavin Davies | 159 | 2036 | 149835 |
Daniel Thomas | 134 | 846 | 84224 |
Will J. Percival | 129 | 473 | 87752 |
Claudia Maraston | 103 | 362 | 59178 |
I. W. Harry | 98 | 312 | 65338 |
Timothy Clark | 95 | 1137 | 53665 |
Kevin Schawinski | 95 | 376 | 30207 |
Ashley J. Ross | 90 | 248 | 46395 |
Josep Call | 90 | 451 | 34196 |
David A. Wake | 89 | 214 | 46124 |
L. K. Nuttall | 89 | 253 | 54834 |
Stephen Neidle | 89 | 457 | 32417 |
Andrew Lundgren | 88 | 249 | 57347 |
Rita Tojeiro | 87 | 229 | 43140 |