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arXiv · hep-ph/0507107

Semi-inclusive radiative decays of Upsilon 1S

Xavier Garcia i Tormo·Joan Soto
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Abstract

We discuss in detail the photon spectrum of radiative Upsilon 1S decays taking into account a number of results that have recently appeared in the literature. In particular, we show how to consistently combine expressions which are valid in the upper end-point region, where NRQCD factorization breaks down, with those of the central region, where NRQCD factorization holds. An excellent description of data is achieved, but theoretical errors are large.

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Xavier Garcia i Tormo, Joan Soto. 2005-09-22. Semi-inclusive radiative decays of Upsilon 1S. https://doi.org/10.1103/physrevd.72.054014

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