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Practical solution to the Monte Carlo sign problem: Realistic calculations of 54Fe

Y. Alhassid·D. J. Dean·S. E. Koonin·G. Lang·W. E. Ormand
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Abstract

We present a practical solution to the "sign problem" in the auxiliary field Monte Carlo approach to the nuclear shell model. The method is based on extrapolation from a continuous family of problem-free Hamiltonians. To demonstrate the resultant ability to treat large shell-model problems, we present results for 54Fe in the full fp-shell basis using the Brown-Richter interaction. We find the Gamow-Teller beta^+ strength to be quenched by 58% relative to the single-particle estimate, in better agreement with experiment than previous estimates based on truncated bases.

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Y. Alhassid, D. J. Dean, S. E. Koonin, G. Lang, W. E. Ormand. 1993-12-22. Practical solution to the Monte Carlo sign problem: Realistic calculations of 54Fe. https://doi.org/10.1103/physrevlett.72.613

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