A program for deriving recoupling coefficients formulae

✍ Scribed by P.M. Lima

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 706 KB
• Volume: 66
• Category: Article
• ISSN: 0010-4655
• DOI: 10.1016/0010-4655(91)90010-i

✦ Synopsis

The program we describe in this paper derives the formulae needed to evaluate the recoupling coefficients which arise in the calculation of matrix elements by the methods of Racach algebra, using the graphical techniques introduced by Jucys et al. and El-Bar et al.. The recoupling coefficients are represented by diagrams, which are stored in the computer memory in the form of arrays. These diagrams are transformed according to given rules, so that any diagram may be decomposed into a product of simple standard diagrams. Using this method, any given recoupling coefficient may be expressed as a weighted sum of 6j-symbols products, affected by phase factors. The obtained formulae are stored in such a form that they may be directly used by another program to calculate the concrete values of the coefficients.