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arXiv · 1305.7217

The kaon semileptonic form factor with near physical domain wall quarks

Peter A. Boyle·Jonathan M. Flynn·Nicolas Garron·Andreas Juttner·Chris T. Sachrajda·Karthee Sivalingam·James M. Zanotti
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Abstract

We present a new calculation of the K->pi semileptonic form factor at zero momentum transfer in domain wall lattice QCD with Nf=2+1 dynamical quark flavours. By using partially twisted boundary conditions we simulate directly at the phenomenologically relevant point of zero momentum transfer. We perform a joint analysis for all available ensembles which include three different lattice spacings (a=0.09-0.14fm), large physical volumes (m_pi*L>3.9) and pion masses as low as 171 MeV. The comprehensive set of simulation points allows for a detailed study of systematic effects leading to the prediction f+(0)=0.9670(20)(+18/-46), where the first error is statistical and the second error systematic. The result allows us to extract the CKM-matrix element |Vus|=0.2237(+13/-8) and confirm first-row CKM-unitarity in the Standard Model at the sub per mille level.

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Peter A. Boyle, Jonathan M. Flynn, Nicolas Garron, Andreas Juttner, Chris T. Sachrajda, Karthee Sivalingam, James M. Zanotti. 2013-05-30. The kaon semileptonic form factor with near physical domain wall quarks. https://doi.org/10.1007/jhep08(2013)132

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