28 July 2020 to 6 August 2020
virtual conference
Europe/Prague timezone

Measurement of absolute branching fractions of $B \to K + X_{cc}$

29 Jul 2020, 17:20
15m
virtual conference

virtual conference

Talk 06. Strong Interactions and Hadron Physics Strong Interactions and Hadron Physics

Speaker

Fergus Wilson (Science and Technology Facilities Council STFC (GB))

Description

We present measurements of absolute branching fractions of the two-body decays of $B$ mesons $B \to K + X_{cc}$, where $X_{cc}$ is a charmonium state, by using a data set corresponding to about 470 fb$^{-1}$ collected by the $BABAR$ detector at the PEP-II $e^+e^-$ collider. For events in which one $B$ is fully reconstructed, the charmonium spectrum can be observed in an unbiased way by looking at the distribution of the $K$ momentum in the rest frame of the recoiling $B$.
The absolute branching fraction $B^+ \to K^+ X(3872)$ is measured for the first time at 3-sigma level, and from it a branching fraction for $BF(X(3872)\to J/\psi \pi^+ \pi^-) = (4.1\pm 1.3)\%$ is derived, supporting the hypothesis of a molecular component for this resonance.

Primary author

Fergus Wilson (Science and Technology Facilities Council STFC (GB))

Presentation Materials