The BABAR calorimeter light pulser system

To make precision measurements with a CsI(Tl) calorimeter in a high-luminos ity environment requires that the crystals are well calibrated and continua lly monitored for radiation damage. This should not impact the total integr ated luminosity which is particularly important for the BABAR calorimeter t o enable it to make CP violation measurements in the B meson system. To ach ieve this goal a fibre-optic light pulser system was designed using xenon f lash lamps as the light sourer. A novel light distribution method was devel oped using an array of graded index microlenses. Some initial results from performance studies are presented. (C) 2001 Elsevier Science B.V. All right s reserved.