# A measurement of the $B^0 \rightarrow J/\psi\pi^+\pi^-$ branching fraction

Abstract : We present a preliminary measurement of the branching fraction for the decay of the neutral $B$ meson into the final state J/$\psi\pi^+\pi^-$. The data set contains approximately 56 million $B\bar{B}$ pairs produced at the $\Upsilon(4S)$ resonance and recorded by the BaBar detector at the PEP-II $e^+e^-$ collider. The result of this analysis is $\mathcal{B}(B^0\to J/\psi\pi^+\pi^-$) = (5.0 $\pm$ 0.7 $\pm$ 0.6)$\times 10^{-5}$, where the first error is statistical and the second is systematic.
Document type :
Conference papers

http://hal.in2p3.fr/in2p3-00011493
Contributor : Claudine Bombar <>
Submitted on : Friday, May 3, 2002 - 4:11:11 PM
Last modification on : Wednesday, January 6, 2021 - 6:22:02 PM

### Citation

B. Aubert, D. Boutigny, J.M. Gaillard, A. Hicheur, Y. Karyotakis, et al.. A measurement of the $B^0 \rightarrow J/\psi\pi^+\pi^-$ branching fraction. Rencontres de Moriond on QCD and Hadronic Interactions 37, Mar 2002, Les Arcs, France. pp.1-16. ⟨in2p3-00011493⟩

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