Black-hole bombs at the LHC

A particle scattered off by a rotating black hole can be amplified when the system is in the superradiant regime. If the system is surrounded by a mirror which reflects the particle back to the black hole the whole system forms a black-hole bomb, amplifying the original field exponentially. We show in this paper that higher dimensional black holes can also form black-hole bombs at the LHC. For a pion the $e$-folding time for the field amplification is $t_c\sim 10^{-23}-10^{-24}$ sec. If the lifetime of the black hole is long enough compared with $t_c$, we can observe severely amplified fields.