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arXiv · 1905.03355

The Stochastic Feynman-Hellmann Method

Arjun Singh Gambhir·Evan Berkowitz·David Brantley·Chia Cheng Chang·M. A. Clark·Thorsten Kurth·Chris Monahan·Amy Nicholson·Pavlos Vranas·André Walker-Loud
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Abstract

The Feynman-Hellmann method, as implemented by Bouchard et al. [1612.06963], was recently employed successfully to determine the nucleon axial charge. A limitation of the method was the restriction to a single operator and a single momentum during the computation of each "Feynman- Hellmann" propagator. By using stochastic techniques to estimate the all-to-all propagator, we relax this constraint and demonstrate the successful implementation of this new method. We show reproduction of the axial charge on a test ensemble and non-zero momentum transfer points of the axial and vector form factors.

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Arjun Singh Gambhir, Evan Berkowitz, David Brantley, Chia Cheng Chang, M. A. Clark, Thorsten Kurth, Chris Monahan, Amy Nicholson, Pavlos Vranas, André Walker-Loud. 2019-05-08. The Stochastic Feynman-Hellmann Method. https://arxiv.org/abs/1905.03355

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