We have studied the energy-energy angular correlations in hadronic final states from Z0 decay using the DELPHI detector at LEP. From a comparison with Monte Carlo calculations based on the exact second order QCD matrix element and string fragmentation we find that Lambda-MS(5) = 104(-20)+25(stat.)-20(+25)(syst.)-00(+30)(theor.) MeV, which corresponds to alpha-s(91 GeV) = 0.106 +/- 0.003(stat.) +/- 0.003(syst.)-0.000(+0.003)(theor.). The theoretical error stems from different choices for the renormalization scale of alpha-s. In the Monte Carlo simulation the scale of alphA-s as well as the fragmentation parameters have been optimized to described reasonably well as aspects of multihadron production.
Energy Energy Correlations In Hadronic Final-states From Z0 Decays
GASPARINI, UGO;RONCHESE, PAOLO;SIMONETTO, FRANCO;ZUMERLE, GIANNI;
1990
Abstract
We have studied the energy-energy angular correlations in hadronic final states from Z0 decay using the DELPHI detector at LEP. From a comparison with Monte Carlo calculations based on the exact second order QCD matrix element and string fragmentation we find that Lambda-MS(5) = 104(-20)+25(stat.)-20(+25)(syst.)-00(+30)(theor.) MeV, which corresponds to alpha-s(91 GeV) = 0.106 +/- 0.003(stat.) +/- 0.003(syst.)-0.000(+0.003)(theor.). The theoretical error stems from different choices for the renormalization scale of alpha-s. In the Monte Carlo simulation the scale of alphA-s as well as the fragmentation parameters have been optimized to described reasonably well as aspects of multihadron production.Pubblicazioni consigliate
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