U501: Beta-Term in Wigner's D-Function

Author(s): K.S. Kölbig Library: MATHLIB
Submitter: Submitted: 15.02.1989
Language: Fortran Revised: 01.12.1994

Function subprograms RDJMNB and DDJMNB calculate the tex2html_wrap_inline104 -term tex2html_wrap_inline106 in the matrix element of the finite rotation operator (Wigner's D-function)

displaymath110

by using the formula (Ref. 1, No. 4.3.1(3))
tex2html_wrap_inline112
tex2html_wrap_inline114
for arbitrary (either all integer or all half-integer) values of j,m,n such that tex2html_wrap_inline118 and tex2html_wrap_inline120 . The summation over k runs from tex2html_wrap_inline124 to tex2html_wrap_inline126 .

On computers other than CDC or Cray, only the double-precision version DDJMNB is available. On CDC and Cray computers, only the single-precision version RDJMNB is available.

Structure:

FUNCTION subprograms
User Entry Names: RDJMNB, DDJMNB
Obsolete User Entry Names: DJMNB tex2html_wrap_inline128 RDJMNB
Files Referenced: Unit 6
External References: MTLMTR, ABEND

Usage:

In any arithmetic expression,

RDJMNB(AJ,AM,AN,BETA) or DDJMNB(AJ,AM,AN,BETA) has the value tex2html_wrap_inline130 ,

where tex2html_wrap_inline132 , tex2html_wrap_inline134 , tex2html_wrap_inline136 and tex2html_wrap_inline138 . RDJMNB is of type REAL, DDJMNB is of type DOUBLE PRECISION, and AJ, AM, AN, BETA have the same type as the function name. BETA has to be given in degrees.

Restrictions:

tex2html_wrap_inline140 , tex2html_wrap_inline142 , tex2html_wrap_inline144 , tex2html_wrap_inline146 .

Accuracy:

Approximately full single- or double-precision machine accuracy, at least for small values of the indices.

Error handling:

Error U501.1: If any of the restrictions is not satisfied, the function value is set equal to zero, and a message is written on Unit 6, unless subroutine MTLSET (N002) has been called.

References:

  1. D.A. Varshalovich, A.N. Moskalev and V.K. Khersonskii, Quantum theory of angular momentum, (World Scientific, Singapore 1988) 76
tex2html_wrap_inline148

Michel Goossens Wed Jun 5 08:22:21 METDST 1996