1. Convergence of Magnus integral addition theorems for confluent hypergeometric functions
- Author
-
Hans Volkmer, Howard S. Cohl, and Jessica E. Hirtenstein
- Subjects
Pure mathematics ,Confluent hypergeometric function ,Hypergeometric function of a matrix argument ,Applied Mathematics ,010102 general mathematics ,Mathematical analysis ,Mathematics::Classical Analysis and ODEs ,010103 numerical & computational mathematics ,Parabolic cylinder function ,Generalized hypergeometric function ,01 natural sciences ,Article ,Barnes integral ,Meijer G-function ,Mathematics - Classical Analysis and ODEs ,Coulomb wave function ,Classical Analysis and ODEs (math.CA) ,FOS: Mathematics ,0101 mathematics ,Hypergeometric function ,Analysis ,33C10, 33C15 ,Mathematics - Abstract
In 1946, Magnus presented an addition theorem for the confluent hypergeometric function of the second kind $U$ with argument $x+y$ expressed as an integral of a product of two $U$'s, one with argument $x$ and another with argument $y$. We take advantage of recently obtained asymptotics for $U$ with large complex first parameter to determine a domain of convergence for Magnus' result. Using well-known specializations of $U$, we obtain corresponding integral addition theorems with precise domains of convergence for modified parabolic cylinder functions, and Hankel, Macdonald, and Bessel functions of the first and second kind with order zero and one.
- Published
- 2022