  A search has been performed for long-lived particles that have stopped in the
CMS detector, during 7 TeV proton-proton operations of the CERN LHC. The
existence of such particles could be inferred from observation of their decays
when there were no proton-proton collisions in the CMS detector, namely during
gaps between LHC beam crossings. Using a data set in which CMS recorded an
integrated luminosity of 4.0 inverse femtobarns, and a search interval
corresponding to 246 hours of trigger live time, 12 events are observed, with a
mean background prediction of 8.6 +/- 2.4 events. Limits are presented at 95%
confidence level on long-lived gluino and stop production, over 13 orders of
magnitude of particle lifetime. Assuming the "cloud model" of R-hadron
interactions, a gluino with mass below 640 GeV and a stop with mass below 340
GeV are excluded, for lifetimes between 10 microseconds and 1000 seconds.
