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arXiv · 0806.2344

Measurement of the eta'-meson mass using J/psi--> gamma eta'

CLEO Collaboration·J. Libby
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Abstract

We measure the mass of the eta' meson using psi(2S)--> pi+ pi- J/psi, J/psi--> gamma eta' events acquired with the CLEO-c detector operating at the CESR e+e- collider. Using three decay modes, eta'--> rho0 gamma, eta'--> pi+ pi- eta with eta--> gamma gamma, and eta'--> pi+ pi- eta with eta--> pi+ pi- pi0, we find M(eta') = 957.793 +- 0.054 +- 0.036 MeV, in which the first uncertainty is statistical and the second is systematic. This result is consistent with but substantially more precise than the current world average.

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CLEO Collaboration, J. Libby. 2008-10-30. Measurement of the eta'-meson mass using J/psi--> gamma eta'. https://doi.org/10.1103/physrevlett.101.182002

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