We present a search for the decay B(+)->tau(+)nu using 383x10(6) B (B) over bar pairs collected at the Upsilon(4S) resonance with the BABAR detector at the SLAC PEP-II B Factory. We select a sample of events with one completely reconstructed tag B in a hadronic decay mode (B(-)-> D((*)0)X(-)), and examine the rest of the event to search for a B(+)->tau(+)nu decay. We identify the tau lepton in the following modes: tau(+)-> e(+)nu<overline>nu</overline>, tau(+)->mu(+)nu(nu) over bar, tau(+)->pi(+)(nu) over bar, and tau(+)->pi(+)pi(0)(nu) over bar. We find a 2.2 sigma excess in data and measure a branching fraction of B(B(+)->tau(+)nu)=(1.8(-0.8)(+0.9)(stat.)+/- 0.4(bkg. syst.)+/- 0.2(other syst.))x10(-4). We calculate the product of the B meson decay constant f(B) and [V(ub)] to be f(B)center dot[V(ub)]=(10.1(-2.5)(+2.3)(stat.)(-1.5)(+1.2)(syst.))x10(-4) GeV.
Search for B(+)->tau(+)nu decays with hadronic B tags RID C-5223-2009 RID C-5719-2008 RID D-1055-2009
LUSIANI, Alberto;
2008
Abstract
We present a search for the decay B(+)->tau(+)nu using 383x10(6) B (B) over bar pairs collected at the Upsilon(4S) resonance with the BABAR detector at the SLAC PEP-II B Factory. We select a sample of events with one completely reconstructed tag B in a hadronic decay mode (B(-)-> D((*)0)X(-)), and examine the rest of the event to search for a B(+)->tau(+)nu decay. We identify the tau lepton in the following modes: tau(+)-> e(+)nuI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
