A time-of-flight technique has been used to search for neutral weakly interacting massive particles in the wideband neutrino beam at the Fermilab Tevatron. Limits at the 90% confidence level are reported herein for (a) heavy neutrino production from the decay of heavy quark states, (b) massive objects directly produced in 800 GeV/c pN interactions that are noninteracting but unstable with a mean lifetime between ${10}^{\mathrm{-}8}$ and ${10}^{\mathrm{-}4}$ s, and (c) directly produced massive objects that are stable but weakly interacting with interaction cross sections between ${10}^{\mathrm{-}29}$ and ${10}^{\mathrm{-}31}$ ${\mathrm{cm}}^2$.

• Received 29 December 1994

DOI:https://doi.org/10.1103/PhysRevD.52.6