MEASUREMENT OF THE STRONG COUPLING CONSTANT ALPHA-s FROM A STUDY OF W BOSONS PRODUCED IN ASSOCIATION WITH JETS

Abstract The UA2 experiment at the CERN p p Collider has identified a total sample of 251 W→eν events. Among this sample 221 events are found without jets and 29 with one jet. The yield of one-jet events relative to that of zero-jet events provides a measurement of the strong coupling constant: α s ( M w 2 )=0.13±0.03(stat)±0.03±(syst 1 )±0.02(syst 2 ), where syst 1 represents the experimental systematic error and syst 2 is an estimate of the theoretical uncertainty.