Performance and Monitering of Zero Degree Calorimeter at CMS

The CMS Zero Degree Calorimeter is designed to measure photons and neutrons for pp and PbPb collisions at TeV energies. The detector can be used for physics and for measuring the brightness and luminosity of the beams. This poster will show the performance of the calorimeter in test beams and describe the monitoring systems we have developed to ensure that the calorimeter is working correctly.