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The First Moment of the Kaon Distribution Amplitude from N_f=2+1 Domain Wall Fermions

P. A. Boyle·M. A. Donnellan·J. M. Flynn·A. Juttner·J. Noaki·C. T. Sachrajda·R. J. Tweedie
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Abstract

We present a lattice computation of the first moment of the kaon's leading-twist distribution amplitude. We use ensembles with 2+1 dynamical flavours of domain wall fermions and the Iwasaki gauge action from the RBC and UKQCD joint dataset. We observe the expected chiral behaviour and obtain <ξ>(2GeV)=3/5a_K^1(2GeV)=0.032(3), which agrees very well with other results obtained using QCD sum-rules and the recent lattice result from the UKQCD/QCDSF collaboration.

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P. A. Boyle, M. A. Donnellan, J. M. Flynn, A. Juttner, J. Noaki, C. T. Sachrajda, R. J. Tweedie. 2006-10-03. The First Moment of the Kaon Distribution Amplitude from N_f=2+1 Domain Wall Fermions. https://arxiv.org/abs/hep-lat/0610025

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