New Structures in the $J\mathrm{/}\psi$ $J\mathrm{/}\psi$ Mass Spectrum at CMS

A search is reported for structures near the $J\mathrm{/}\psi$ $J\mathrm{/}\psi$ mass threshold using a dataset of proton-proton collisions at $\sqrt{s}=13\mathrm{T}\mathrm{e}\mathrm{V}$ recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of about $135\mathrm{f}{\mathrm{b}}^{-1}$. Two structures are observed with a significance exceeding $5\sigma$ and evidence of an additional structure is reported with a local significance of $4.7\sigma$.