Lawrence Berkeley National Laboratory

A search is presented for massive long-lived particles, in the 20–60 GeV/c2$${\mathrm {Ge V\!/}c^2}$$ mass range with lifetimes between 5 and 100 ps$$\mathrm{ps}$$. The dataset used corresponds to 0.62fb-1$$ \text{ fb }^{-1}$$ of proton-proton collision data collected by the LHCb detector at s=7TeV$$\sqrt{s} =7\mathrm {\,Te V} $$. The particles are assumed to be pair-produced by the decay of a Higgs-like boson with mass between 80 and 140 GeV/c2$${\mathrm {Ge V\!/}c^2}$$. No excess above the background expectation is observed and limits are set on the production cross-section as a function of the long-lived particle mass and lifetime and of the Higgs-like boson mass.