A Search for B -> K(*) nu nubar and Invisible Quarkonium Decays
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
(2)
,
P. Roudeau
(2)
,
M.H. Schune
(2)
,
A. Stocchi
(2)
,
G. Wormser
(2)
,
D. Bernard
(3)
,
M. Verderi
(3)
,
S. Emery
(4)
,
G. Hamel de Monchenault
(4)
,
G. Vasseur
(4)
,
Ch. Yèche
(4)
,
S. Akar
(5)
,
E. Ben-Haim
(5)
,
M. Bomben
(5)
,
G.R. Bonneaud
(5)
,
H. Briand
(5)
,
G. Calderini
(5)
,
J. Chauvau
(5)
,
O. Hamon
(5)
,
Ph. Leruste
(5)
,
G. Marchiori
(5)
,
J. Ocariz
(5)
,
S. Sitt
(5)
N. Arnaud
- Function : Author
- PersonId : 16841
- IdHAL : nicolas-arnaud
- ORCID : 0000-0001-6589-8673
G. Vasseur
- Function : Author
- PersonId : 745439
- IdHAL : georges-vasseur
M. Bomben
- Function : Author
- PersonId : 1380362
- ORCID : 0000-0002-9807-861X
- IdRef : 242005462
G. Calderini
- Function : Author
- PersonId : 10608
- IdHAL : giovanni-calderini
- ORCID : 0000-0002-9495-9145
- IdRef : 172243211
G. Marchiori
- Function : Author
- PersonId : 741274
- IdHAL : giovanni-marchiori
- ORCID : 0000-0003-2655-7643
- IdRef : 180997203
Abstract
We search for the flavor-changing neutral-current decays B->K(*)\nu\nu, and the invisible decays J/psi->\nu\nu\ and psi(2S)->\nu\nu\ via B->K(*)J/psi and B->K(*)psi(2S) respectively, using a data sample of 471 x10^6 BB pairs collected by the BaBar experiment. We fully reconstruct the hadronic decay of one of the B mesons in the Upsilon(4S)->BB decay, and search for the B->K(*)\nu\nu\ decay in the rest of the event. We observe no significant excess of signal decays over background and report branching fraction upper limits of BR(B+->K+\nu\nu)<3.7 x10^-5, BR(B0->K0\nu\nu)< 8.1 x10^-5, BR(B+->K*+\nu\nu)<11.6 x10^-5, BR(B0->K*0\nu\nu)<9.3 x10^-5, and combined upper limits of BR(B->K\nu\nu)<3.2 x10^-5 and BR(B->K*\nu\nu)<7.9 x10^-5, all at the 90% confidence level. For the invisible quarkonium decays, we report branching fraction upper limits of BR(J/psi->\nu\nu)<3.9 x10^-3 and BR(psi(2S)->\nu\nu)<15.5 x10^-3 at the 90% confidence level. Using the improved kinematic resolution achieved from hadronic reconstruction, we also provide partial branching fraction limits for the B->K(*)\nu\nu\ decays over the full kinematic spectrum.