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arXiv · 2001.05366

Structure functions from the Compton amplitude

CSSM collaboration·Roger Horsley·Yoshifumi Nakamura·Holger Perlt·Paul E. L. Rakow·Gerrit Schierholz·Kim Somfleth·Ross D. Young·James M. Zanotti
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Abstract

We have initiated a program to compute the Compton amplitude from lattice QCD with the Feynman-Hellman method. This amplitude is related to the structure function via a Fredholm integral equation of the first kind. It is known that these types of equations are inherently ill--posed - they are, e.g., extremely sensitive to perturbations of the system. We discuss two methods which are candidates to handle these problems: the model free inversion based on singular value decomposition and one Bayesian type approach. We apply the Bayesian method to currently available lattice data for the Compton amplitude.

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CSSM collaboration, Roger Horsley, Yoshifumi Nakamura, Holger Perlt, Paul E. L. Rakow, Gerrit Schierholz, Kim Somfleth, Ross D. Young, James M. Zanotti. 2020-01-15. Structure functions from the Compton amplitude. https://arxiv.org/abs/2001.05366

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