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Number of states with fixed angular momentum for identical fermions and bosons

Y. M. Zhao·A. Arima
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Abstract

We present in this paper empirical formulas for the number of angular momentum I states for three and four identical fermions or bosons. In the cases with large I we prove that the number of states with the same ${\cal M}$ and n but different J is identical if $I \ge (n-2)J - {1/2} (n-1)(n-2)$ for fermions and $I \ge (n-2)J$ for bosons, and that the number of states is also identical for the same ${\cal M}$ but different n and J if ${\cal M} \le $min(n, 2J+1 - n) for fermions and for ${\cal M} \le $min(n, 2J) for bosons. Here ${\cal M} =I_{max}-I$, n is the particle number, and J refers to the angular momentum of a single-particle orbit for fermions, or the spin L carried by bosons.

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Y. M. Zhao, A. Arima. 2003-04-14. Number of states with fixed angular momentum for identical fermions and bosons. https://doi.org/10.1103/physrevc.68.044310

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