TY - JOUR
T1 - Update on the sea contributions to hadron polarizabilities via reweighting
AU - Freeman, Walter
AU - Alexandru, Andrei
AU - Lee, Frank X.
AU - Lujan, Michael
N1 - Funding Information:
This calculation was done on the GWU Colonial One and IMPACT GPU clusters and the Fermilab GPU cluster. This work is supported in part by the NSF CAREER grant PHY-1151648 and the U.S. Department of Energy grant DE-FG02-95ER-40907.
Publisher Copyright:
© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.
PY - 2014
Y1 - 2014
N2 - We have made significant progress on extending lattice QCD calculation of the polarizability of the neutron and other hadrons to include the effects of charged dynamical quarks. This is done by perturbatively reweighting the charges of the sea quarks to couple them to the background field. The dominant challenge in such a calculation is stochastic estimation of the weight factors, and we discuss the difficulties in this estimation. Here we use an extremely aggressive dilution scheme with N = 124,416 sources per configuration to reduce the stochastic noise to a manageable level. We find that αE = 2.70(55) × 10∼-4fm3 for the neutron on one ensemble. We show that lowmode substitution can be used in tandem with dilution to construct an even better estimator, and introduce the offdiagonal matrix element mapping technique for predicting estimator quality.
AB - We have made significant progress on extending lattice QCD calculation of the polarizability of the neutron and other hadrons to include the effects of charged dynamical quarks. This is done by perturbatively reweighting the charges of the sea quarks to couple them to the background field. The dominant challenge in such a calculation is stochastic estimation of the weight factors, and we discuss the difficulties in this estimation. Here we use an extremely aggressive dilution scheme with N = 124,416 sources per configuration to reduce the stochastic noise to a manageable level. We find that αE = 2.70(55) × 10∼-4fm3 for the neutron on one ensemble. We show that lowmode substitution can be used in tandem with dilution to construct an even better estimator, and introduce the offdiagonal matrix element mapping technique for predicting estimator quality.
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M3 - Conference Article
AN - SCOPUS:85030090415
SN - 1824-8039
VL - Part F130500
JO - Proceedings of Science
JF - Proceedings of Science
M1 - 154
T2 - 32nd International Symposium on Lattice Field Theory, LATTICE 2014
Y2 - 23 June 2014 through 28 June 2014
ER -