D ec 1 99 3 Practical solution to the Monte Carlo sign problem : Realistic calculations of 54 Fe
نویسندگان
چکیده
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 54 Fe in the full f p-shell basis using the Brown-Richter interaction. We find the Gamow-Teller β + 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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