Observation of a peaking structure in the J /ψφ mass spectrum from B ± → J /ψφ K ± decays

A peaking structure in the J /ψφ mass spectrum near threshold is observed in B ± → J /ψφ K ± decays, produced in pp collisions at √ s = 7 TeV collected with the CMS detector at the LHC. The data sample, selected on the basis of the dimuon decay mode of the J /ψ , corresponds to an integrated luminosity of 5.2 fb − 1 . Fitting the structure to an S -wave relativistic Breit–Wigner lineshape above a three-body phase-space nonresonant component gives a signal statistical significance exceeding five standard deviations. The fitted mass and width values are m = 4148 . 0 ± 2 . 4 ( stat. ) ± 6 . 3 ( syst. ) MeV and Γ = 28 + 15 − 11 ( stat. ) ± 19 ( syst. ) MeV, respectively. Evidence for an additional peaking structure at higher J /ψφ mass is also reported.

[1]  H. K. Wöhri,et al.  Heavy quarkonium: progress, puzzles, and opportunities , 2010, 1010.5827.

[2]  D. Volyanskyy,et al.  CMS tracking performance results from early LHC operation , 2010, 1007.1988.

[3]  Gui-Jun Ding.  Possible molecular states of $D^{*}_{s}\bar{D}^{*}_{s}$ system and Y(4140) , 2009, 0904.1782.

[4]  Xiang Liu.  The hidden charm decay of Y (4140) by the rescattering mechanism , 2009, 0904.0136.

[5]  M. Nielsen,et al.  A QCD sum rule calculation for the Y(4140) narrow structure , 2009, 0903.5540.

[6]  T. Gutsche,et al.  Hadronic molecule structure of the Y(3940) and Y(4140) , 2009, 0903.5424.

[7]  Zhi-Gang wang.  Analysis of the Y(4140) with QCD sum rules , 2009, 0903.5200.

[8]  N. Mahajan.  Y(4140): Possible options , 2009, 0903.3107.

[9]  Xiang Liu,et al.  Y(4143) is probably a molecular partner of Y(3930) , 2009, 0903.2529.

[10]  João Paulo Teixeira,et al.  The CMS experiment at the CERN LHC , 2008 .

[11]  R. Seuster.  Recent results from Belle , 2004, hep-ex/0411036.

[12]  D. Bernard.  Recent Results of BABAR , 2001, hep-ex/0111022.

[13]  D. Lange,et al.  The EvtGen particle decay simulation package , 2001 .

[14]  A. González-Arroyo,et al.  Diffractive Production of Strange Mesons at 63-{GeV} , 1981 .

[15]  P. Barria,et al.  Evidence for a Narrow Near-Threshold Structure in the J/ψφ Mass Spectrum in B + → J/ψφK + Decays , 2009 .

[16]  J. Rademacker,et al.  Observation of the narrow state X (3872) → J/Ψπ + π - in anti- p p collisions at sqrt[ s ] = 1.96 TeV , 2004 .