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231.
Recurrence spectra of He atoms in strong external fields 总被引:1,自引:0,他引:1
LIN Shenglu LI Hongyun WANG Dehua ZHAO Wenli & GAO Feng . Department of Physics Shandong Normal University Jinan China . Department of Mathematics Physics Shandong Institute of Architecture Engineering Jinan China 《中国科学G辑(英文版)》2004,47(4):477-484
1 Introduction The photo-absorption phenomenon of high Rydberg atoms in strong external fields has attracted much attention in recent years. The semiclassical closed-orbit theory[1,2] developed by Du and Delos has been extensively used to explain this phenomenon. This theory has successfully calculated and interpreted the photo-absorption spectra of H- in various external fields[3,4] and has been applied to describe the photo-excitation, wave packet dynamics of some atoms and molecules such… 相似文献
232.
Two linearly independent asymptotic solutions are constructed for the second-order linear difference equation
where and have power series expansions of the form
with . Our results hold uniformly for in an infinite interval containing the transition point given by . As an illustration, we present an asymptotic expansion for the monic polynomials which are orthogonal with respect to the modified Jacobi weight , , where , -1$"> and is real analytic and strictly positive on .
where and have power series expansions of the form
with . Our results hold uniformly for in an infinite interval containing the transition point given by . As an illustration, we present an asymptotic expansion for the monic polynomials which are orthogonal with respect to the modified Jacobi weight , , where , -1$"> and is real analytic and strictly positive on .
233.
Xia Chen 《Probability Theory and Related Fields》2000,116(1):89-123
Let {X
n
}
n
≥0 be a Harris recurrent Markov chain with state space E and invariant measure π. The law of the iterated logarithm and the law of weak convergence are given for the additive functionals
of the form
where ƒ is a real π-centered function defined on E. Some similar results are also obtained for additive functionals which are martingales associated with {X
n
}
n
≥0.
Received: 15 September 1998 / Revised version: 1 April 1999 相似文献
234.
文献[1]给出了一个三项单指标的常系数齐次递推式的一般解公式。本文一类带双指标的变系数非齐次递推关系的解的结构。其结果,对双指标的相应递推关系式的解的求出,亦或在其有关理论的研究方面,皆有其作用。 相似文献
235.
Mark Westcott 《Journal of statistical physics》1982,27(1):75-82
This paper discusses the mean-square displacement for a random walk on a two-dimensional lattice, whose transitions to nearest-neighbor sites are symmetric in the horizontal and vertical directions and depend on the column currently occupied. Under a uniform density condition for the step probabilities it is shown that the horizontal mean-square displacement aftern steps is asymptotically proportional ton, and independent of the particular column configuration. The model generalizes that of Seshadri, Lindenberg, and Shuler and the arguments are essentially probabilistic. 相似文献
236.
A numerical method for the solution of the Abel integral equation is presented. The known function is approximated by a sum of Chebyshev polynomials. The solution can then be expressed as a sum of generalized hypergeometric functions, which can easily be evaluated, using a simple recurrence relation. 相似文献
237.
This paper deals with the bilinear symmetrization problem associated with Sobolev inner products. Let 007B;Q
n
}
n=0
be the sequence of monic polynomials orthogonal with respect to a Sobolev inner product of order 1 when one of the measures is discrete and the other one is a nondiscrete positive Borel measure. Furthermore, assume that the supports of such measures are symmetric with respect to the origin so that the corresponding odd moments vanish. We consider the orthogonality properties of the sequences of monic polynomials 007B;P
n
}
n=0
and {R
n
}
n=0
such that Q
2n
(x)=P
n
(x
2), Q
2n+1(x)=xR
n
(x
2). Moreover, recurrence relations for {P
n
}
n=0
and {R
n
}
n=0
are obtained as well as explicit algebraic relations between them. 相似文献
238.
S. B. Damelin. 《Mathematics of Computation》2004,73(245):191-209
We use Freud equations to obtain the main term in the asymptotic expansion of the recurrence coefficients associated with orthonormal polynomials for weights on the real line where is an even polynomial of fixed degree with nonnegative coefficients or where . Here for some real -1$">.
239.
240.
Guillaume Hanrot. 《Mathematics of Computation》2000,69(229):395-405
The main problem when solving a Thue equation is the computation of the unit group of a certain number field. In this paper we show that the knowledge of a subgroup of finite index is actually sufficient. Two examples linked with the primitive divisor problem for Lucas and Lehmer sequences are given.