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Test of the Flavour Independence of alpha_s using Next-to-Leading Order Calculations for Heavy Quarks

The OPAL Collaboration·G. Abbiendi et al
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Abstract

We present a test of the flavour independence of the strong coupling constant for charm and bottom quarks with respect to light (uds) quarks, based on a hadronic event sample obtained with the OPAL detector at LEP. Five observables related to global event shapes were used to measure alpha_s in three flavour tagged samples (uds, c and b). The event shape distributions were fitted by Order(alpha_s**2) calculations of jet production taking into account mass effects for the c and b quarks. We find: = 0.997 +- 0.038(stat.) +- 0.030(syst.) +- 0.012(theory) and = 0.993 +- 0.008(stat.) +- 0.006(syst.) +- 0.011(theory) for the ratios alpha_s(charm)/alpha_s(uds) and alpha_s(b)/alpha_s(uds) respectively.

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The OPAL Collaboration, G. Abbiendi et al. 1999-04-13. Test of the Flavour Independence of alpha_s using Next-to-Leading Order Calculations for Heavy Quarks. https://doi.org/10.1007/s100520050661

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