Search for the X(5568) State Decaying into B_s⁰ π^± in Proton-Proton Collisions at √s = 8 TeV

Abstract

A search for resonancelike structures in the \({B}_{s}^{0}{\pi }^{±}\) invariant mass spectrum is performed using proton-proton collision data collected by the CMS experiment at the LHC at \(\sqrt{s}=8\text{}\text{}\mathrm{TeV}\), corresponding to an integrated luminosity of \(19.7\text{}\text{}{\mathrm{fb}}^{-1}\). The \({B}_{s}^{0}\) mesons are reconstructed in the decay chain \({B}_{s}^{0}\to J/\psi \varphi \), with \(J/\psi \to {\mu }^{+}{\mu }^{-}\) and \(\varphi \to {K}^{+}{K}^{-}\). The \({B}_{s}^{0}{\pi }^{±}\) invariant mass distribution shows no statistically significant peaks for different selection requirements on the reconstructed \({B}_{s}^{0}\) and \({\pi }^{±}\) candidates. Upper limits are set on the relative production rates of the \(X\left(5568\right)\) and \({B}_{s}^{0}\) states times the branching fraction of the decay \(X\left(5568{\right)}^{±}\to {B}_{s}^{0}{\pi }^{±}\). In addition, upper limits are obtained as a function of the mass and the natural width of possible exotic states decaying into \({B}_{s}^{0}{\pi }^{±}\).