Nonperturbative corrections to B→Xsℓ+ℓ− with phase space restrictions

We study nonperturbative corrections up to O(1/mb3) in the inclusive rare B decay B→Xsℓ+ℓ− by performing an operator product expansion. The values of the matrix elements entering at this order are unknown and introduce uncertainties into physical quantities. Imposing a phase space cut to eliminate the cc̄ resonances we find that the O(1/mb3) corrections introduce an O(10%) uncertainty in the measured rate. We also find that the contributions arising at O(1/mb3) are comparable to the ones arising at O(1/mb2) over the entire region of phase space.