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arXiv · 1212.2564

The effects of flavour symmetry breaking on hadron matrix elements

A. N. Cooke·R. Horsley·Y. Nakamura·D. Pleiter·P. E. L. Rakow·G. Schierholz·J. M. Zanotti
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Abstract

By considering a flavour expansion about the SU(3)-flavour symmetric point, we investigate how flavour-blindness constrains octet baryon matrix elements after SU(3) is broken by the mass difference between the strange and light quarks. We find the expansions to be highly constrained along a mass trajectory where the singlet quark mass is held constant, which proves beneficial for extrapolations of 2+1 flavour lattice data to the physical point. We investigate these effects numerically via a lattice calculation of the flavour-conserving and flavour-changing matrix elements of the vector and axial operators between octet baryon states.

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A. N. Cooke, R. Horsley, Y. Nakamura, D. Pleiter, P. E. L. Rakow, G. Schierholz, J. M. Zanotti. 2012-12-11. The effects of flavour symmetry breaking on hadron matrix elements. https://arxiv.org/abs/1212.2564

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