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arXiv · 1310.4426

Update on the Sea Contributions to Hadron Electric Polarizabilities through Reweighting

Walter Freeman·Andrei Alexandru·Mike Lujan·Frank X. Lee
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Abstract

We present the results of a reweighting calculation to compute the contribution of the charged quark sea to the neutron electric polarizability. The chief difficulty is the stochastic estimation of weight factors, and we present a hopping parameter expansion-based technique for reducing the stochastic noise, along with a discussion of why this particular reweighting is so difficult. We used this technique to estimate weight factors for 300 configurations of nHYP-clover fermions and compute the neutron polarizability, but the reweighting greatly inflates the overall statistical error, driven by the stochastic noise in the weight factors.

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Walter Freeman, Andrei Alexandru, Mike Lujan, Frank X. Lee. 2013-10-16. Update on the Sea Contributions to Hadron Electric Polarizabilities through Reweighting. https://arxiv.org/abs/1310.4426

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