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تسجيل مستخدم جديدA lattice determination of Sigma - Lambda mixing
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Isospin breaking effects in baryon octet (and decuplet) masses are due to a combination of up and down quark mass differences and electromagnetic effects and lead to small mass splittings. Between the Sigma and Lambda this mass splitting is much larger, this being mostly due to their different wavefunctions. However when isospin is broken, there is a mixing between between these states. We describe the formalism necessary to determine the QCD mixing matrix and hence find the mixing angle and mass splitting between the Sigma and Lambda particles due to QCD effects.
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In this Reply, we respond to the above Comment. Our computation [Phys. Rev. D 91 (2015) 074512] only took into account pure QCD effects, arising from quark mass differences, so it is not surprising that there are discrepancies in isospin splittings a
nd in the Sigma - Lambda mixing angle. We expect that these discrepancies will be smaller in a full calculation incorporating QED effects.
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 t
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arger, but this is mostly due to their different wavefunctions. However there is now also mixing between these states. We determine the QCD mixing matrix and hence find the mixing angle and mass splitting.
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