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arXiv · 1611.01383

Computing the nucleon Dirac radius directly at $Q^2=0$

Nesreen Hasan·Michael Engelhardt·Jeremy Green·Stefan Krieg·Stefan Meinel·John Negele·Andrew Pochinsky·Sergey Syritsyn
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Abstract

We describe a lattice approach for directly computing momentum derivatives of nucleon matrix elements using the Rome method, which we apply to obtain the isovector magnetic moment and Dirac radius. We present preliminary results calculated at the physical pion mass using a 2HEX-smeared Wilson-clover action. For removing the effects of excited-state contamination, the calculations were done at three source-sink separations and the summation method was used.

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Nesreen Hasan, Michael Engelhardt, Jeremy Green, Stefan Krieg, Stefan Meinel, John Negele, Andrew Pochinsky, Sergey Syritsyn. 2016-11-04. Computing the nucleon Dirac radius directly at $Q^2=0$. https://arxiv.org/abs/1611.01383

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