  A search is presented for massive long-lived particles decaying into a muon
and two quarks. The dataset consists of proton-proton interactions at
centre-of-mass energies of 7 and 8 TeV, corresponding to integrated
luminosities of 1 and 2 1/fb, respectively. The analysis is performed assuming
a set of production mechanisms with simple topologies, including the production
of a Higgs-like particle decaying into two long-lived particles. The mass range
from 20 to 80 GeV and lifetimes from 5 to 100 ps are explored. Results are also
interpreted in terms of neutralino production in different supersymmetric
models, with masses in the 23-198 GeV range. No excess above the background
expectation is observed and upper limits are set on the production
cross-section for various points in the parameter space of theoretical models.
