Test of the flavour independence of αs
D Buskulic, D Casper, I De Bonis, D Decamp, P Ghez, C Goy, JP Lees, MN Minard, P Odier, B Pietrzyk, F Ariztizabal, M Chmeissani, JM Crespo, I Efthymiopoulos, E Fernandez, M Fernandez-Bosman, V Gaitan, L Garrido, M Martinez, S Orteu Show all
Physics Letters B | Published : 1995
Using about 950000 hadronic events collected during 1991 and 1992 with the ALEPH detector, the ratios rb = αsb αsudsc and ruds = αsuds αscb have been measured in order to test the flavour independence of the strong coupling constant αs. The analysis is based on event-shape variables using the full hadronic sample, two b-quark samples enriched by lepton tagging and lifetime tagging, and a light-quark sample enriched by lifetime antitagging. The combined results are rb = 1.002±0.023 and ruds = 0.971 ± 0.023. © 1995.