-annihilation Event

نویسنده

  • K. Tesima
چکیده

The collimation C of a hadronic event in the e + e −-annihilation is defined as the average of cos θ, C =< cos θ >, 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−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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تاریخ انتشار 1997