@article{a60fcaf115c941d3a794826550d3bed7,

title = "Observation of the resonant character of the $Z(4430)^-$ state",

abstract = " Resonant structures in $B^0\to\psi'\pi^-K^+$ decays are analyzed by performing a four-dimensional fit of the decay amplitude, using $pp$ collision data corresponding to $\rm 3 fb^{-1}$ collected with the LHCb detector. The data cannot be described with $K^+\pi^-$ resonances alone, which is confirmed with a model-independent approach. A highly significant $Z(4430)^-\to\psi'\pi^-$ component is required, thus confirming the existence of this state. The observed evolution of the $Z(4430)^-$ amplitude with the $\psi'\pi^-$ mass establishes the resonant nature of this particle. The mass and width measurements are substantially improved. The spin-parity is determined unambiguously to be $1^+$. ",

keywords = "hep-ex",

author = "{LHCb Collaboration} and LHCb collaboration and R. Aaij and B. Adeva and M. Adinolfi and A. Affolder and Z. Ajaltouni and J. Albrecht and F. Alessio and G. Alkhazov and Cartelle, {P. Alvarez} and Jr, {A. A. Alves} and S. Amato and S. Amerio and Y. Amhis and L. An and L. Anderlini and R. Andreassen and M. Andreotti and Appleby, {R. B.} and Gutierrez, {O. Aquines} and F. Archilli and A. Artamonov and M. Artuso and E. Aslanides and G. Auriemma and M. Baalouch and S. Bachmann and Back, {J. J.} and A. Badalov and V. Balagura and W. Baldini and C. Barschel and S. Barsuk and J. Benton and Brook, {N. H.} and M. Coombes and S. Cunliffe and J. Dalseno and T. Hampson and Harnew, {S. T.} and P. Naik and K. Petridis and C. Prouve and Rademacker, {J. H.} and Molina, {V. Rives} and N. Skidmore and P. Szczypka and Velthuis, {J. J.} and D. Voong and Wilson, {F. F.}",

note = "10 pages, 4 figures",

year = "2014",

month = jun,

day = "6",

doi = "10.1103/PhysRevLett.112.222002",

language = "English",

volume = "112",

pages = "222002",

journal = "Physical Review Letters",

issn = "0031-9007",

publisher = "American Physical Society (APS)",

number = "22",

}