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A Counterexample to a Generalized Saari's Conjecture with a Continuum of Central Configurations 总被引:1,自引:1,他引:0
Manuele Santoprete 《Celestial Mechanics and Dynamical Astronomy》2004,89(4):357-364
In this paper we show that in the n-body problem with harmonic potential one can find a continuum of central configurations for n= 3. Moreover we show a counterexample to an interpretation of Jerry Marsden Generalized Saari's conjecture. This will help
to refine our understanding and formulation of the Generalized Saari's conjecture, and in turn it might provide insight in
how to solve the classical Saari's conjecture for n≥ 4.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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天体周日视运动过程中天体的高度不断变化,对天体观测的质量有直接的影响,通过分析天体周日视运动过程中天体高度的变化率,给出不同观测时机进行天体高度观测的特性,并用曲线图的形式给出天体高度变化率的极值点和零值点。航海人员可以从更深的层次认识天体周日视运动的规律,指导天文定位过程中对天体高度的观测。 相似文献
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G. I.Ogilvie 《Monthly notices of the Royal Astronomical Society》2002,330(4):937-949
The non-axisymmetric features observed in the discs of dwarf novae in outburst are usually considered to be spiral shocks, which are the non-linear relatives of tidally excited waves. This interpretation suffers from a number of problems. For example, the natural site of wave excitation lies outside the Roche lobe, the disc must be especially hot, and most treatments of wave propagation do not take into account the vertical structure of the disc.
In this paper I construct a detailed semi-analytical model of the non-linear tidal distortion of a thin, three-dimensional accretion disc by a binary companion on a circular orbit. The analysis presented here allows for vertical motion and radiative energy transport, and introduces a simple model for the turbulent magnetic stress. The m =2 inner vertical resonance has an important influence on the amplitude and phase of the tidal distortion. I show that the observed patterns find a natural explanation if the emission is associated with the tidally thickened sectors of the outer disc, which may be irradiated from the centre. According to this hypothesis, it may be possible to constrain the physical parameters of the disc through future observations. 相似文献
In this paper I construct a detailed semi-analytical model of the non-linear tidal distortion of a thin, three-dimensional accretion disc by a binary companion on a circular orbit. The analysis presented here allows for vertical motion and radiative energy transport, and introduces a simple model for the turbulent magnetic stress. The m =2 inner vertical resonance has an important influence on the amplitude and phase of the tidal distortion. I show that the observed patterns find a natural explanation if the emission is associated with the tidally thickened sectors of the outer disc, which may be irradiated from the centre. According to this hypothesis, it may be possible to constrain the physical parameters of the disc through future observations. 相似文献
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Summary of results from a high - resolution pan - Arctic ice - ocean model are presented for the northern North Pacific, Bering, Chukchi, and Beaufort seas. The main focus is on the mean circulation, communication from the Gulf of Alaska across the Bering Sea into the western Arctic Ocean and on mesoscale eddy activity within several important ecosystems. Model results from 1979 -2004 are compared to observations whenever possible. The high spatial model resolution at 1/12o (or -9 - km) in the horizontal and 45 levels in the vertical direction allows for representation of eddies with diameters as small as 36 km. However, we believe that upcoming new model integrations at even higher resolution will allow us to resolve even smaller eddies. This is especially important at the highest latitudes where the Rossby radius of deformation is as small as 10 km or less. 相似文献