Search for exclusive photoproduction of Z$_c^{\pm}$(3900) at COMPASS
arXiv:1407.6186 · doi:10.1016/j.physletb.2015.01.042
Abstract
A search for the exclusive production of the $Z_c^{\pm}(3900)$ hadron by virtual photons has been performed in the channel $Z_c^{\pm}(3900)\rightarrow J/ÏÏ^{\pm}$. The data cover the range from 7 GeV to 19 GeV in the centre-of-mass energy of the photon-nucleon system. The full set of the COMPASS data set collected with a muon beam between 2002 and 2011 has been used. An upper limit for the ratio $BR(Z_c^{\pm}(3900)\rightarrow J/ÏÏ^{\pm} )\times Ï_{ γ~N \rightarrow Z_c^{\pm}(3900)~ N} /Ï_{γ~N \rightarrow J/Ï~ N}$ of $3.7\times10^{-3}$ has been established at the confidence level of 90%.
8 pages, 3 figures, 1 table