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Extrapolation method in shell model calculations with deformed basis

Takahiro Mizusaki
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Abstract

An extrapolation method in shell model calculations with deformed basis is presented, which uses a scaling property of energy and energy variance for a series of systematically approximated wave functions to the true one. Such approximated wave functions are given by variation-after-projection method concerning the full angular momentum projection. This extrapolation needs energy variance, which amounts to the calculation of expectation value of square of Hamiltonian $\hat{H}^2$. We present the method to evaluate this matrix element and show that large reduction of its numerical computation can be done by taking an advantage of time-reversal symmetry. The numerical tests are presented for $fp$ shell calculations with a realistic residual interaction.

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Takahiro Mizusaki. 2004-08-27. Extrapolation method in shell model calculations with deformed basis. https://doi.org/10.1103/physrevc.70.044316

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