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Octet contributions in radiative upsilon decays

Xavier Garcia i Tormo
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Abstract

We analyze the end-point region of the photon spectrum in semi-inclusive radiative decays of very heavy quarkonium (m alpha_s^2 >> Lambda_QCD). The S- and P-wave octet shape functions are calculated. When they are included in the analysis of the photon spectrum of the Upsilon (1S) system the agreement with data becomes excellent.

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Xavier Garcia i Tormo. 2004-10-04. Octet contributions in radiative upsilon decays. https://arxiv.org/abs/hep-ph/0410052

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