The UA1 Collaboration has recently improved its measurement of the beauty production cross-section by including explicit measurements of bb̄ correlations. Using these data we have determined the strong coupling constant αs. The comparison of the measured cross-section for 2-body final states with O(α3s) QCD predictions yields a measurement of αs(20 GeV) = 0.145+0.012 +0.013-0.010 exp -0.016 th, corresponding to αs(Mz) = 0.1131+0.007 +0.008-0.006 exp -0.009 th. This is the first theoretically well-defined measurement of αs from a purely hadronic production process. Evaluating αs from cross-sections at different Q2-values we find that the running of αs is needed for internal consistency of the UA1 data.
|Original language||English (US)|
|Number of pages||9|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|State||Published - Feb 15 1996|
Bibliographical noteFunding Information:
We are thankful to the managementa nd staff of CERN and of all participating institutes for their vigorous support of the experiment.T he following funding agenciesh ave contributed to this programme: Fonds zur Fiirderung der Wissenschaftlichen Forschung, Austria; Valtion luonnontieteellinen toimikunta, Suomen Akatemia, Finland; Institut National de Physique Nucleaire et de Physique des Particules and Institut de Recherche Fondamen-tale (CEA), France; Bundesministerium fur Forschung und Technologie, Germany; Istituto Nationale di Fisica Nucleare, Italy; Science and Engineering Research Council, United Kingdom; Stichting Voor FundamenteelO nderzoek der Materie, The Netherlands; Centro de Investigaciones Energetica,M edioambien-tales y Tecnologicas (CIEMAT), Spain; Departmento f Energy, USA.