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arXiv · 1501.06347

Analytical formula for numerical evaluations of the Wigner rotation matrices at high spins

Naoki Tajima
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Abstract

The Wigner d function, which is the essential part of an irreducible representation of SU(2) and SO(3) parameterized with Euler angles, has been know to suffer from a serious numerical errors at high spins, if it is calculated by means of the Wigner formula as a polynomial of cos and sin of half of the second Euler angle. This paper shows a way to avoid this problem by expressing the d functions as the Fourier series of the half angle. A precise numerical table of the coefficients of the series is obtainable from a web site.

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Naoki Tajima. 2015-01-26. Analytical formula for numerical evaluations of the Wigner rotation matrices at high spins. https://doi.org/10.1103/physrevc.91.014320

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