Pile-up detector for LHCb

99-014 In this article we propose to use a dedicated pile-up detector --- 180 degree Cherenkov calorimeter which measures energies of gamma-quanta being produced in ppinteractions by the Cherenkov radiation intensity --- to ensure the conditions which will allow LHCb to work with luminosity 4--5 10 32 cm -2 s -1 . The calorimeter consists of a multiplicator with the width corresponding to the maximum of particles in an electromagnetic shower, behind which a quartz plate is situated where shower particles produce Cherenkov radiation. The pile-up detector is situated at the 180 degree angle relative to the LHCb spectrometer.