We have searched for D-0-(D) over bar (0) mixing in D{*}(+)->pi D-+(0) decays with D-0 -> K-({*}())e nu in a sample of e(+)e(-)-> c (c) over bar events produced near 10.58 GeV. The charge of the slow pion from charged D{*} decay tags the charm flavor at production, and it is required to be consistent with the flavor of a fully reconstructed second charm decay in the same event. We observe 3 mixed candidates compared to 2.85 background events expected from simulation. We ascribe a 50\% systematic uncertainty to this expected background rate. We find a central value for the mixing rate of 0.4x10(-4). Using a frequentist method, we set corresponding 68\% and 90\% confidence intervals at (-5.6,7.4)x10(-4) and (-13,12)x10(-4), respectively.
Search for D-0-(D-0)over bar mixing using doubly flavor tagged semileptonic decay modes
BIANCHI, Fabrizio;GAMBA, Diego;
2007-01-01
Abstract
We have searched for D-0-(D) over bar (0) mixing in D{*}(+)->pi D-+(0) decays with D-0 -> K-({*}())e nu in a sample of e(+)e(-)-> c (c) over bar events produced near 10.58 GeV. The charge of the slow pion from charged D{*} decay tags the charm flavor at production, and it is required to be consistent with the flavor of a fully reconstructed second charm decay in the same event. We observe 3 mixed candidates compared to 2.85 background events expected from simulation. We ascribe a 50\% systematic uncertainty to this expected background rate. We find a central value for the mixing rate of 0.4x10(-4). Using a frequentist method, we set corresponding 68\% and 90\% confidence intervals at (-5.6,7.4)x10(-4) and (-13,12)x10(-4), respectively.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.