We present a search for the lepton flavor violating decay B+-> K+tau(-/+)mu(+/-) using 383x10(6) B (B) over bar events collected by the BABAR experiment. The branching fraction for this decay can be substantially enhanced in new physics models. The kinematics of the tau from the signal B decay are inferred from the K+, mu, and other B in the event, which is fully reconstructed in one of a variety of hadronic decay modes, allowing the signal B candidate to be fully reconstructed. We observe no excess of events over the expected background and set a limit of B(B+-> K+tau mu)< 7.7x10(-5) at 90% confidence level, where the branching fraction is for the sum of the K+tau(-)mu(+) and K+tau(+)mu(-) final states. We use this result to improve a model-independent bound on the energy scale of flavor-changing new physics.
Search for the decay B+-> K+tau(-/+)mu(+/-) RID C-5223-2009 RID C-5719-2008 RID D-1055-2009
LUSIANI, Alberto;
2007
Abstract
We present a search for the lepton flavor violating decay B+-> K+tau(-/+)mu(+/-) using 383x10(6) B (B) over bar events collected by the BABAR experiment. The branching fraction for this decay can be substantially enhanced in new physics models. The kinematics of the tau from the signal B decay are inferred from the K+, mu, and other B in the event, which is fully reconstructed in one of a variety of hadronic decay modes, allowing the signal B candidate to be fully reconstructed. We observe no excess of events over the expected background and set a limit of B(B+-> K+tau mu)< 7.7x10(-5) at 90% confidence level, where the branching fraction is for the sum of the K+tau(-)mu(+) and K+tau(+)mu(-) final states. We use this result to improve a model-independent bound on the energy scale of flavor-changing new physics.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
