Ghosts of the Milky Way: a search for topology in new quasar catalogues     

S. J. Weatherley  S. J. Warren  S. M. Croom  R. J. Smith  B. J. Boyle  T. Shanks  L. Miller  M. P. Baltovic 《Monthly notices of the Royal Astronomical Society》2003,342(1):L9-L13

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Optical flashes and very early afterglows in wind environments     

X. F. Wu  Z. G. Dai  Y. F. Huang  T. Lu 《Monthly notices of the Royal Astronomical Society》2003,342(4):1131-1138

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Coronal change at the south-west limb observed by Yohkoh on 9 November 1991, and the subsequent interplanetary shock at Pioneer Venus Orbiter     

Shinichi Watari  Z. Smith  H. A. Garcia  T. Detman  M. Dryer 《Solar physics》1996,167(1-2):357-369

A spectacular change in the lower corona on the south-west limb has been found in solar images taken by the Yohkoh soft X-ray telescope. The event is characterized by a large topological change in magnetic field and a large intensity decrease observed after the X1. 1/1B flare on 9 November, 1991. A coronal mass ejection (CME) was observed by the Mark III K-coronameter (MK3) at the HAO/Mauna Loa Observatory. Both the MK3 (white-light) and soft X-ray observations showed that one leg of this CME was located above the flare site. An interplanetary shock associated with this event was observed by Pioneer Venus Orbiter, and, possibly, by IMP-8.Also Cooperative Institute for Research in the Environmental Sciences (CIRES), University of Colorado, Boulder, CO 80309, U.S.A.  相似文献   

Book reviews     

Howard  R. F.  van den Oord  G. H. J.  Švestka  Z. 《Solar physics》1996,169(1):225-227

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Spectroscopy of comet P/Schaumasse     

Neal James Joung Turner  Graeme H. Smith 《Earth, Moon, and Planets》1996,73(1):33-50

Column density profiles for CN, C₃, C₂ and NH have been determined from a long-slit CCD spectrum of periodic comet P/Schaumasse (1992x). Comparisons of these profiles with Haser models indicate that the ratios of the CN, C₃ and C₂ production rates are typical for a short-period comet. Although the scale lengths for NH and its parent species are uncertain, the results indicate that the production rate for NH is much greater than for either C₂ or CN.  相似文献   

The geochemistry of lead in rivers,estuaries and the continental shelf of the Southeastern United States     

Herbert L Windom  Ralph G Smith  Masaru Maeda 《Marine Chemistry》1985,17(1):43-56

Transport by southeastern rivers has insignificant influence on the lead concentration of southeastern shelf waters. If the rate of mobilization and transport of lead by these rivers is representative of uncontaminated fluvial transport during the Pleistocene, only about 5% of the prehistoric output of lead to the North Atlantic can be accounted for by river input.Lead concentrations in southeastern shelf waters are similar to those of North Atlantic Water from the upper 1000 m, which is probably similar to the intrusion source water for the shelf. Atmospheric inputs to the shelf of the same magnitude as observed for the Western North Atlantic are difficult to reconcile given the residence time of shelf waters and their lead concentration unless the rate of loss of lead to shelf sediments is about the same as the atmospheric flux.  相似文献   

Population synthesis for symbiotic stars with white dwarf accretors     

Guoliang Lü  L. Yungelson  Z. Han 《Monthly notices of the Royal Astronomical Society》2006,372(3):1389-1406

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Single star scidar: atmospheric parameters profiling using the simulated annealing algorithm     

A. Habib  J. Vernin  Z. Benkhaldoun  H. Lanteri 《Monthly notices of the Royal Astronomical Society》2006,368(3):1456-1462

In this paper, we present a new method to estimate, for each turbulent layer labelled i , the horizontal wind speed   v ( h _i )  , the standard deviation of the horizontal wind speed fluctuations  σ _v ( h_i )  and the integrated value of   C ² _n   over the thickness  Δ h_i   of the turbulent layer   C ² _n ( h_i )Δ h_i   , where   h_i   is the altitude of the turbulent layer. These parameters are extracted from single star scintillation spatiotemporal cross-correlation functions of atmospheric speckles obtained within the generalized mode. This method is based on the simulated annealing algorithm to find the optimal solution required to solve the problem. Astrophysics parameters for adaptive optics are also calculated using   C ² _n ( h_i )  and   v ( h_i )  values. The results of other techniques support this new method.  相似文献   

Calibration of the kinematic method of studying solar wind disturbances on the basis of a one-dimensional MHD solution and a simulation study of the heliosphere disturbances between 22 november and 6 december 1977     

Wei Sun  S.-I. Akasofu  Z.K. Smith  M. Dryer 《Planetary and Space Science》1985,33(8):933-943

An empirical kinematic method developed by Hakamada and Akasofu (1982) is calibrated on the basis of a one-dimensional MHD solution. The calibrated results are used to simulate the stream-stream interaction and the background corotating structure in a simple situation and also during 22 November–6 December 1977. The solar wind disturbances caused by solar activities during this period are then introduced into the above background stream in simulating the heliospheric disturbance event which was observed by an aligned set of spacecraft at distances between 0.6 and 1.6 a.u. The observations and the simulated results are satisfactory, and a little more refinement in the simulation could reconstruct reasonably well the data by filling the data gaps in the solar wind speed, the density and the IMF magnitude.  相似文献   

Transient‐state groundwater flow in various geometries with wells at arbitrary positions: analytical methods     

M. W. Roth  C. M Wilson  M. Z. Iqbal 《水文研究》2003,17(17):3519-3530

We have developed a method for analytically solving the porous medium flow equation in many different geometries for horizontal (two‐dimensional), homogeneous and isotropic aquifers containing impermeable boundaries and any number of pumping or injection wells located at arbitrary positions within the system. Solutions and results are presented for rectangular and circular aquifers but the method presented here is easily extendible to many geometries. Results are also presented for systems where constant head boundary conditions can be emulated internal to the aquifer boundary. Recommendations for extensions of the present work are briefly discussed. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献