SR power calorimetry and photon measurements at the photodesorption beam line of the VEPP-2M storage ring

Measurements of synchrotron radiation beam power and its reflectivity from the walls of a transport beam line were performed at the gas photodesorption beam line of the storage ring VEPP-2M. Measurements of radiation power and induced photo-electron current were applied in these experiments. It is shown that the measured power of the synchrotron radiation beam is in agreement with the calculated one within the measurement errors, and effects of radiation reflection from the beam line walls are negligible. The obtained results indicate that the calculated values of the power and the photon flux for a direct synchrotron radiation beam can be used, with a quite acceptable accuracy, in gas photodesorption experiments.