Search for the Z(4430)[superscript -] at BABAR

Abstract

We report the results of a search for Z(4430)- decay to J/psi pi- or psi(2S)pi - in B-,0→J/psi pi-K0,+ and B-,0-->psi(2S)pi-K0,+ decays. The data were collected with the BABAR detector at the SLAC PEP-II asymmetric-energy e+e- collider operating at center-of-mass energy 10.58 GeV, and the sample corresponds to an integrated luminosity of 413 fb[superscript -1]. Each Kpi- mass distribution exhibits clear K*(892) and K[subscript 2]*(1430) signals, and the efficiency-corrected spectrum is well described by a superposition of the associated Breit-Wigner intensity distributions, together with an S-wave contribution obtained from the LASS I=1/2 Kpi- scattering amplitude measurements. Each Kpi- angular distribution varies significantly in structure with Kpi- mass, and is represented in terms of low-order Legendre polynomial moments. We find that each J/psi pi- or psi(2S)pi- mass distribution is well described by the reflection of the measured Kπ- mass and angular distribution structures. We see no significant evidence for a Z(4430)- signal for any of the processes investigated, neither in the total J/psi pi- or psi(2S)pi- mass distribution, nor in the corresponding distributions for the regions of Kpi- mass for which observation of the Z(4430)- signal was reported. We obtain branching-fraction upper limits B(B- -->Z-K[over-bar] 0,Z-→J/psi pi-)<1.5×10[superscript -5], B(B0-->Z-K+,Z- -->J/psi pi-)<0.4×10[superscript -5], B(B- -->Z-K[over-bar] 0,Z- -->psi(2S)pi-)<4.7×10[superscript -5], and B(B0-->Z-K+,Z--->psi(2S)pi-)<3.1×10[superscript -5] at 95% confidence level, where the Z(4430)- mass and width have been fixed to the reported central values.