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arXiv · 1903.12590

Light-cone distribution amplitudes of octet baryons from lattice QCD

Abstract

We present lattice QCD results for the wave function normalization constants and the first moments of the distribution amplitudes for the lowest-lying baryon octet. The analysis is based on a large number of $N_f=2+1$ ensembles comprising multiple trajectories in the quark mass plane including physical pion (and kaon) masses, large volumes, and, most importantly, five different lattice spacings down to $a=0.039\,\mathrm{fm}$. This allows us to perform a controlled extrapolation to the continuum and infinite volume limits by a simultaneous fit to all available data. We demonstrate that the formerly observed violation of flavor symmetry breaking constraints can, indeed, be attributed to discretization effects that vanish in the continuum limit.

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Gunnar S. Bali, Vladimir M. Braun, Simon Bürger, Sara Collins, Meinulf Göckeler, Michael Gruber, Fabian Hutzler, Piotr Korcyl, Andreas Schäfer, Wolfgang Söldner, André Sternbeck, Philipp Wein. 2019-07-23. Light-cone distribution amplitudes of octet baryons from lattice QCD. https://doi.org/10.1140/epja%2Fi2019-12803-6

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