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, Poison control, Fuzzy logic
Papers published on a yearly basis
Papers
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École Polytechnique Fédérale de Lausanne1, Paris Diderot University2, University of California, Irvine3, Lawrence Berkeley National Laboratory4, Brookhaven National Laboratory5, Max Planck Society6, University of Portsmouth7, New Mexico State University8, University of Utah9, Harvard University10, University of Barcelona11, Aix-Marseille University12, University of Wyoming13, Pierre-and-Marie-Curie University14, Carnegie Mellon University15, Institut d'Astrophysique de Paris16, Drexel University17, Sejong University18, Pennsylvania State University19, Ohio State University20, University of Chicago21
TL;DR: In this paper, a detection of the baryon acoustic oscillation (BAO) feature in the flux-correlation function of the Ly forest of high-redshift quasars with a statistical significance of five standard deviations was reported.
Abstract: We report a detection of the baryon acoustic oscillation (BAO) feature in the flux-correlation function of the Ly forest of high-redshift quasars with a statistical significance of five standard deviations The study uses 137,562 quasars in the redshift range 2:1 z 3:5 from the Data Release 11 (DR11) of the Baryon Oscillation Spectroscopic Survey (BOSS) of SDSS-III This sample contains three times the number of quasars used in previous studies The measured position of the BAO peak determines the angular distance, DA(z = 2:34) and expansion rate, H(z = 2:34), both on a scale set by the sound horizon at the drag epoch, rd We find DA=rd =
871 citations
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TL;DR: In this article, a local rotation in field space is performed to separate out the adiabatic and entropy modes, and the resulting field equations show explicitly how on large scales entropy perturbations can source adiabaatic perturbation if the background solution follows a curved trajectory in the field space.
Abstract: We study adiabatic ~curvature! and entropy ~isocurvature! perturbations produced during a period of cosmological inflation that is driven by multiple scalar fields with an arbitrary interaction potential. A local rotation in field space is performed to separate out the adiabatic and entropy modes. The resulting field equations show explicitly how on large scales entropy perturbations can source adiabatic perturbations if the background solution follows a curved trajectory in field space, and how adiabatic perturbations cannot source entropy perturbations in the long-wavelength limit. It is the effective mass of the entropy field that determines the amplitude of entropy perturbations during inflation. We present two applications of the equations. First, we show why one in general expects the adiabatic and entropy perturbations to be correlated at the end of inflation, and calculate the cross correlation in the context of a double inflation model with two non-interacting fields. Second, we consider two-field preheating after inflation, examining conditions under which entropy perturbations can alter the large-scale curvature perturbation and showing how our new formalism has advantages in numerical stability when the background solution follows a non-trivial trajectory in field space.
830 citations
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TL;DR: In this article, the authors summarize the recent changes observed in climate elements and cryospheric indicators on the Tibetan Plateau before discussing current unresolved issues concerning climate change in the TP, including the temporal and spatial components of this change, and the consistency of change as represented by different data sources.
Abstract: The Tibetan Plateau (TP), with an average elevation of over 4000 m asl and an area of approximately 2.5 × 10 6 km 2 , is the highest and most extensive highland in the world and has been called the ‘Third Pole’. The TP exerts a huge influence on regional and global climate through thermal and mechanical forcing mechanisms. Because the TP has the largest cryospheric extent outside the polar region and is the source region of all the large rivers in Asia, it is widely recognized to be the driving force for both regional environmental change and amplification of environmental changes on a global scale. Within China it is recognized as the ‘Asian water tower’. In this letter, we summarize the recent changes observed in climate elements and cryospheric indicators on the plateau before discussing current unresolved issues concerning climate change in the TP, including the temporal and spatial components of this change, and the consistency of change as represented by different data sources. Based on meteorological station data, reanalyses and remote sensing, the TP has shown significant warming during the last decades and will continue to warm in the future. While the warming is predominantly caused by increased greenhouse gas emissions, changes in cloud amount, snow-albedo feedback, the Asian brown clouds and land use changes also partly contribute. The cryosphere in the TP is undergoing rapid change, including glacier retreat, inconsistent snow cover change, increasing permafrost temperatures and degradation, and thickening of the active layer. Hydrological processes impacted by glacial retreat have received much attention in recent years. Future attention should be paid to additional perspectives on climate change in the TP, such as the variations of climate extremes, the reliability of reanalyses and more detailed comparisons of reanalyses with surface observations. Spatial issues include the identification of whether an elevational dependency and weekend effect exist, and the identification of spatial contrasts in temperature change, along with their causes. These issues are uncertain because of a lack of reliable data above 5000 m asl.
825 citations
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TL;DR: This work has focused on the influence of biomineralization processes taking place on metallic surfaces and the impact of extracellular enzymes, active within the biofilm matrix, on electrochemical reactions at theBiofilm-metal interface.
817 citations
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TL;DR: The Fifth Data Release (DR5) of the Sloan Digital Sky Survey (SDSS) was released in 2005 June and represents the completion of the SDSS-I project as mentioned in this paper, which includes five-band photometric data for 217 million objects selected over 8000 deg 2 and 1,048,960 spectra of galaxies, quasars, and stars selected from 5713 deg 2 of imaging data.
Abstract: This paper describes the Fifth Data Release (DR5) of the Sloan Digital Sky Survey (SDSS). DR5 includes all survey quality data taken through 2005 June and represents the completion of the SDSS-I project (whose successor, SDSS-II, will continue through mid-2008). It includes five-band photometric data for 217 million objects selected over 8000 deg^2 and 1,048,960 spectra of galaxies, quasars, and stars selected from 5713 deg^2 of that imaging data. These numbers represent a roughly 20% increment over those of the Fourth Data Release; all the data from previous data releases are included in the present release. In addition to "standard" SDSS observations, DR5 includes repeat scans of the southern equatorial stripe, imaging scans across M31 and the core of the Perseus Cluster of galaxies, and the first spectroscopic data from SEGUE, a survey to explore the kinematics and chemical evolution of the Galaxy. The catalog database incorporates several new features, including photometric redshifts of galaxies, tables of matched objects in overlap regions of the imaging survey, and tools that allow precise computations of survey geometry for statistical investigations.
811 citations
Authors
Showing all 5624 results
Name | H-index | Papers | Citations |
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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 |