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arXiv · 1012.0215

Charge Symmetry Breaking in Parton Distribution Functions from Lattice QCD

R. Horsley·Y. Nakamura·D. Pleiter·P. E. L. Rakow·G. Schierholz·H. Stüben·A. W. Thomas·F. Winter·R. D. Young·J. M. Zanotti
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Abstract

By determining the quark momentum fractions of the octet baryons from N_f=2+1 lattice simulations, we are able to predict the degree of charge symmetry violation in the parton distribution functions of the nucleon. This is of importance, not only as a probe of our understanding of the non-perturbative structure of the proton but also because such a violation constrains the accuracy of global fits to parton distribution functions and hence the accuracy with which, for example, cross sections at the LHC can be predicted. A violation of charge symmetry may also be critical in cases where symmetries are used to guide the search for physics beyond the Standard Model.

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R. Horsley, Y. Nakamura, D. Pleiter, P. E. L. Rakow, G. Schierholz, H. Stüben, A. W. Thomas, F. Winter, R. D. Young, J. M. Zanotti. 2010-12-01. Charge Symmetry Breaking in Parton Distribution Functions from Lattice QCD. https://doi.org/10.1103/physrevd.83.051501

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