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arXiv · 1911.02186

Electromagnetic contribution to $\Sigma$-$\Lambda$ mixing using lattice QCD+QED

Z. R. Kordov·R. Horsley·Y. Nakamura·H. Perlt·P. E. L. Rakow·G. Schierholz·H. Stüben·R. D. Young·J. M. Zanotti
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Abstract

Mixing in the $\Sigma^0$-$\Lambda^0$ system is a direct consequence of broken isospin symmetry and is a measure of both isospin-symmetry breaking as well as general SU(3)-flavour symmetry breaking. In this work we present a new scheme for calculating the extent of $\Sigma^0$-$\Lambda^0$ mixing using simulations in lattice QCD+QED and perform several extrapolations that compare well with various past determinations. Our scheme allows us to easily contrast the QCD-only mixing case with the full QCD+QED mixing.

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BibTeXRIS

Z. R. Kordov, R. Horsley, Y. Nakamura, H. Perlt, P. E. L. Rakow, G. Schierholz, H. Stüben, R. D. Young, J. M. Zanotti. 2019-11-06. Electromagnetic contribution to $\Sigma$-$\Lambda$ mixing using lattice QCD+QED. https://doi.org/10.1103/physrevd.101.034517

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