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arXiv · hep-ph/9705238

Collimation of the e^+e^- annihilation event

K. Kimura·K. Tesima
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Abstract

The collimation $C$ of a hadronic event in the e^+e^- annihilation is defined as the average of $\cosθ$, $C=<\cosθ>$, where $θ$ is the angle of each hadron measured from the thrust axis, and the average is over all the hadrons produced in an event. It is an infrared-stable event-shape parameter. $1-\bar C$, the difference between the unity and the average collimation at a given energy, is proportional to the anomalous dimension of the hadron multiplicity at the leading order in MLLA. Its next-to-leading order corrections are calculated.

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K. Kimura, K. Tesima. 1997-05-06. Collimation of the e^+e^- annihilation event. https://arxiv.org/abs/hep-ph/9705238

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