Determinations of α S and tests of analytic hadronisation models using e + e − annihilation data
نویسندگان
چکیده
We report results on measurements of the strong coupling αS from event shape data at PETRA and LEP. Their distributions are analysed employing the new NLLO+NLLA calculations and hadronisation correction by Monte Carlo models using JADE data. This results in a very precise measurement of the strong coupling, αS(mZ0) = 0.1172±0.0051. The running of the strong coupling is confirmed significantly. Analyses of their moments using next to leading order calculations and hadronisation correction by analytical power corrections show shortcomings of the calculations, which can be expected to be alleviated by the NNLO calculations.
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تاریخ انتشار 2009