Model-independent observation of exotic contributions to $B^0\to J/ψK^+π^-$ decays

Abstract

An angular analysis of $B^0\to J/ψK^+π^-$ decays is performed, using proton-proton collision data corresponding to an integrated luminosity of 3~${\rm fb}^{-1}$ collected with the LHCb detector. The $m(K^+π^-)$ spectrum is divided into fine bins. In each $m(K^+π^-)$ bin, the hypothesis that the three-dimensional angular distribution can be described by structures induced only by $K^\ast$ resonances is examined, making minimal assumptions about the $K^+π^-$ system. The data reject the $K^\ast$-only hypothesis with a large significance, implying the observation of exotic contributions in a model-independent fashion. Inspection of the $m(J/ψπ^-)$ versus $m(K^+π^-)$ plane suggests structures near $m(J/ψπ^-)=4200$~MeV and 4600~MeV.

All figures and tables, along with any supplementary material and additional information, are available at http://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2018-043.html