Observation of B+ -> (D)over-bar*(0)tau(+) v(tau) and evidence for B+ -> (D)over-bar(0)tau(+) v(tau) at Belle
2010
Abstract
We present measurements of B+ -> (D) over bar*(0)tau(+) v(tau) and B+ -> (D) over bar (0)tau(+) v(tau) decays in a data sample of 657 x 10(6) B (B) over bar pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We find 446(-56)(+58) B+ -> (D) over bar*(0)tau(+) v(tau) events with a significance of 8.1 standard deviations, and 146(-41)(+42) B+ -> (D) over bar (0)tau(+) v(tau) events with a significance of 3.5 standard deviations.
The latter signal provides the first evidence for this decay mode. The measured branching fractions are B(B+ -> (D) over bar*(0)tau(+) v(tau)) = (2.12(-0.27)(+0.28) (stat) +/- 0.29(syst))% and B(B+ -> (D) over bar (0)tau(+) v(tau) ) = (0.77 +/- 0.22(stat) +/- 0.12(syst))%.