Studies of the solar mean magnetic field with the Birmingham Solar-Oscillations Network (BiSON)   总被引：1，自引：0，他引：1  

W. J. Chaplin  A. M. Dumbill  Y. Elsworth  G. R. Isaak  C. P. McLeod  B. A. Miller  R. New  B. Pintér 《Monthly notices of the Royal Astronomical Society》2003,343(3):813-818

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The Interplay of Cluster and Galaxy Evolution     

R.C. Nichol  Ch.J. Miller  Tomotsugu Goto 《Astrophysics and Space Science》2003,285(1):157-165

We review here the interplay of cluster and galaxy evolution. As a case study, we consider the Butcher-Oemler effect and propose that it is the result of the changing rate of cluster merger events in a hierarchical universe. This case study highlights the need for new catalogs of clusters and groups that possess quantified morphologies. We present such a sample here, namely the Sloan Digital Sky Survey (SDSS) C4 Catalog, which has been objectively-selected from the SDSS spectroscopic galaxy sample. We outline here the C4algorithm and present first results based on the SDSS Early Data Release, including an X-ray luminosity-velocity dispersion (L_x-σ_v) scaling relationship (as a function of cluster morphology) and the density-SFR relation of galaxies within C4 clusters (Gomez et al., 2003). We also discuss the merger of Coma and the NGC4839 group and its effect on the galaxy populations in these systems. We finish with a brief discussion of a new sample ofHΔ-selected galaxies (i.e., k+a, post-starburst galaxies) obtained from the SDSS spectroscopic survey. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Fluvial system response to Late Devensian (Weichselian) aridity,Baston, Lincolnshire,England     

Rebecca M. Briant  G. Russell Coope  Richard C. Preece  David H. Keen  Steve Boreham  Huw I. Griffiths  Mary B. Seddon  Philip L. Gibbard 《第四纪科学杂志》2004,19(5):479-495

Little is known about the impact of Late Devensian (Weichselian) aridity on lowland British landscapes, largely because they lack the widespread coversand deposits of the adjacent continent. The concentration of large interformational ice‐wedge casts in the upper part of many Devensian fluvial sequences suggests that fluvial activity may have decreased considerably during this time. The development of optically stimulated luminescence (OSL) dating enables this period of ice‐wedge cast formation to be constrained for the first time in eastern England, where a marked horizon of ice‐wedge casts is found between two distinctive dateable facies associations. Contrasts between this horizon and adjacent sediments show clear changes in environment and fluvial system behaviour in response to changing water supply, in line with palaeontological evidence. In addition to providing chronological control on the period of ice‐wedge formation, the study shows good agreement of the radiocarbon and OSL dating techniques during the Middle and Late Devensian, with direct comparison of these techniques beyond 15 000 yr for the first time in Britain. It is suggested that aridity during the Late Devensian forced a significant decrease in fluvial activity compared with preceding and following periods, initiating a system with low peak flows and widespread permafrost development. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

The 2dF Galaxy Redshift Survey: correlation functions, peculiar velocities and the matter density of the Universe   总被引：1，自引：0，他引：1  

Ed Hawkins  Steve Maddox  Shaun Cole  Ofer Lahav  Darren S. Madgwick  Peder Norberg  John A. Peacock  Ivan K. Baldry  Carlton M. Baugh  Joss Bland-Hawthorn  Terry Bridges  Russell Cannon  Matthew Colless  Chris Collins  Warrick Couch  Gavin Dalton  Roberto De Propris  Simon P. Driver  George Efstathiou  Richard S. Ellis  Carlos S. Frenk  Karl Glazebrook  Carole Jackson  Bryn Jones  Ian Lewis  Stuart Lumsden  Will Percival  Bruce A. Peterson  Will Sutherland  Keith Taylor 《Monthly notices of the Royal Astronomical Society》2003,346(1):78-96

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Near-infrared imaging and the  K−z  relation for radio galaxies in the 7C Redshift Survey     

Chris J. Willott  Steve Rawlings  Matt J. Jarvis  Katherine M. Blundell 《Monthly notices of the Royal Astronomical Society》2003,339(1):173-188

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Cosmic-ray induced neutrino fluxes at the Moon: A semi-analytic approach     

R.S. Miller  T. Cohen 《Astroparticle Physics》2006,25(6):368-374

Cosmic-ray induced neutrino backgrounds at the Moon are estimated using a semi-analytic approach. The analytic expressions are derived, flux estimates for and are given, and comparisons with the analogous backgrounds generated in the Earth’s atmosphere are presented. Suppression of the lunar fluxes relative to the terrestrial fluxes is found. At energies >10 GeV, the suppression approaches a maximum of order 10⁻⁴. The lower background environment suggests that the Moon may be advantageous for future particle astrophysics endeavors.  相似文献   

Using a topographic index to distribute variable source area runoff predicted with the SCS curve‐number equation     

Steve W. Lyon  M. Todd Walter  Pierre Grard‐Marchant  Tammo S. Steenhuis 《水文研究》2004,18(15):2757-2771

Because the traditional Soil Conservation Service curve‐number (SCS‐CN) approach continues to be used ubiquitously in water quality models, new application methods are needed that are consistent with variable source area (VSA) hydrological processes in the landscape. We developed and tested a distributed approach for applying the traditional SCS‐CN equation to watersheds where VSA hydrology is a dominant process. Predicting the location of source areas is important for watershed planning because restricting potentially polluting activities from runoff source areas is fundamental to controlling non‐point‐source pollution. The method presented here used the traditional SCS‐CN approach to predict runoff volume and spatial extent of saturated areas and a topographic index, like that used in TOPMODEL, to distribute runoff source areas through watersheds. The resulting distributed CN–VSA method was applied to two subwatersheds of the Delaware basin in the Catskill Mountains region of New York State and one watershed in south‐eastern Australia to produce runoff‐probability maps. Observed saturated area locations in the watersheds agreed with the distributed CN–VSA method. Results showed good agreement with those obtained from the previously validated soil moisture routing (SMR) model. When compared with the traditional SCS‐CN method, the distributed CN–VSA method predicted a similar total volume of runoff, but vastly different locations of runoff generation. Thus, the distributed CN–VSA approach provides a physically based method that is simple enough to be incorporated into water quality models, and other tools that currently use the traditional SCS–CN method, while still adhering to the principles of VSA hydrology. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

GMOS IFU observations of the stellar and gaseous kinematics in the centre of NGC 1068     

Joris Gerssen  Jeremy Allington-Smith  Bryan W. Miller  James E. H. Turner  Andrew Walker † 《Monthly notices of the Royal Astronomical Society》2006,365(1):29-36

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Galactic oscillations     

R. H. Miller  B. F. Smith 《Celestial Mechanics and Dynamical Astronomy》1994,59(2):161-199

A stable galaxy, if excited above its ground state, oscillates about that ground state. If it is reasonably robust, it can support oscillations of large amplitude. Normal mode oscillations, with surprisingly large amplitudes, have been seen in numerical experiments. Observational evidence shows that real galaxies also oscillate. Galaxies ring like a bell in the experiments, and ringing continues undamped long after initial transients have died out. Their total kinetic energy oscillates with an amplitude as large as 10% of the mean. A fundamental mode dominates. It is an homologous expansion/contraction of the entire galaxy (no nodes). Inward or outward velocities due to this mode are sufficiently large in the outer reaches of a galaxy to account for kinematic warps in observed velocity fields. A second spherically symmetrical mode has one node and is important near the center of the galaxy. It may be the driving force behind bulges in spiral galaxies. Two other normal modes have been identified as well. This appears to be the first experimental demonstration of normal mode oscillations within stable galaxy models.  相似文献   

Aspects of Observed Gust Factors in Landfalling Tropical Cyclones: Gust Components,Terrain, and Upstream Fetch Effects     

Craig Miller  Juan-Antonio Balderrama  Forrest Masters 《Boundary-Layer Meteorology》2015,155(1):129-155

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