Evidence for the baryonic decay B0bar --> D0 Lambda Lambdabar
J. P. Lees
(1)
,
V. Poireau
(1)
,
V. Tisserand
(1)
,
N. Arnaud
(2)
,
M. Davier
(2)
,
D. Derkach
(2)
,
G. Grosdidier
(2)
,
F. Le Diberder
(2)
,
A.M. Lutz
(2)
,
B. Malaescu
(3)
,
P. Roudeau
(2)
,
M.H. Schune
(2)
,
A. Stocchi
(2)
,
G. Wormser
(2)
,
D. Bernard
(4)
,
M. Verderi
(4)
,
S. Emery
(5)
,
G. Hamel de Monchenault
(5)
,
G. Vasseur
(5)
,
Ch. Yèche
(5)
,
S. Akar
(3)
,
E. Ben-Haim
(3)
,
M. Bomben
(3)
,
G.R. Bonneaud
(3)
,
H. Briand
(3)
,
G. Calderini
(3)
,
J. Chauvau
(3)
,
O. Hamon
(3)
,
Ph. Leruste
(3)
,
G. Marchiori
(3)
,
J. Ocariz
(3)
,
S. Sitt
(3)
N. Arnaud
- Fonction : Auteur
- PersonId : 16841
- IdHAL : nicolas-arnaud
- ORCID : 0000-0001-6589-8673
G. Vasseur
- Fonction : Auteur
- PersonId : 745439
- IdHAL : georges-vasseur
G. Calderini
- Fonction : Auteur
- PersonId : 10608
- IdHAL : giovanni-calderini
- ORCID : 0000-0002-9495-9145
- IdRef : 172243211
G. Marchiori
- Fonction : Auteur
- PersonId : 741274
- IdHAL : giovanni-marchiori
- ORCID : 0000-0003-2655-7643
- IdRef : 180997203
Résumé
Evidence is presented for the baryonic $B$ meson decay $\bar{B}\rightarrow D^0 \Lambda \bar{\Lambda}$ based on a data sample of $471 \times 10^6$ $B\bar{B}$ pairs collected with the {\it BABAR} detector at the PEP2 asymmetric $e^+e^-$ collider located at the SLAC National Accelerator Laboratory. The branching fraction is determined to be $\mathcal{B}(\bar{B}\rightarrow D^0 \Lambda \bar{\Lambda}) = (9.8^{+2.9}_{-2.6} \pm 1.9)\times 10^{-6}$, corresponding to a significance of $3.4$ standard deviations including systematic uncertainties. A search for the related baryonic $B$ meson decay $\bar{B}\rightarrow D^0 \Sigma^0 \bar{\Lambda}$ with $\Sigma^0\rightarrow\Lambda\gamma$ is performed and an upper limit $\mathcal{B}(\bar{B}\rightarrow D^0 \Sigma^0 \bar{\Lambda} + \bar{B}\rightarrow D^0 \Lambda \bar{\Sigma}^0) < 3.1 \times 10^{-5}$ is determined at $90\%$ confidence level.