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arXiv · hep-lat/0607032

The decay constant of the first excited pion from lattice QCD

UKQCD Collaboration·C. McNeile·C. Michael
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Abstract

We review the theory that predicts that the decay constant of the excited light pseudo-scalar mesons are suppressed in the chiral limit relative to the pion decay constant. We compute the decay constant of the first excited pion ($π^\prime$) using unquenched QCD at a fixed lattice spacing with sea quarks of mass as low as a third the mass of the strange quark. The final result is very sensitive to the improvement conditions. We obtain $f_{π^\prime} / f_π$ = 0.078(93) in the chiral limit.

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UKQCD Collaboration, C. McNeile, C. Michael. 2006-08-10. The decay constant of the first excited pion from lattice QCD. https://doi.org/10.1016/j.physletb.2006.09.056

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