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arXiv · hep-ph/9608244

Relativistic and Binding Energy Corrections to Direct Photon Production In Upsilon Decay

Mohammad Ali Yusuf·Pervez Hoodbhoy
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Abstract

A systematic gauge-invariant method is used to calculate the rate for an upsilon meson to decay inclusively into a prompt photon. An expansion is made in the quark relative velocity v, which is a small natural parameter for heavy quark systems. Inclusion of these O(v^2) corrections tends to increase the photon rate in the middle z range and to lower it for larger z, a feature supported by the data.

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Mohammad Ali Yusuf, Pervez Hoodbhoy. 1996-08-06. Relativistic and Binding Energy Corrections to Direct Photon Production In Upsilon Decay. https://doi.org/10.1103/physrevd.54.3345

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