DSSC Prototype Ladder Operation and Performance Study at PETRA III/P04

The DSSC (DEPFET Sensor with Signal Compression) is a new instrument with non-linear response and with parallel signal processing (filtering, linear amplification, and 8-bit digitization) for all pixels. The DSSC will serve as ultra-fast megapixel imaging detector at the European XFEL (X-ray Free Electron Laser) in Schenefeld, Germany, which began science operation in September this year. In December 2016, at the Variable Polarization XUV Beamline (PO4) of PETRA III, the Synchrotron Radiation Source at DESY in Hamburg, Germany, a prototype ladder system with 128 x 512 pixels was operated and studied for the first time. The prototype system could be operated and read-out continuously throughout the beamtime. First studies of the performance of the prototype ladder system were performed using the collected data. For example, we measured for the first time the system gain for different coarse ASIC gain settings, and studied the dispersion of the gain in a 17 x 57 pixel sensor sub-matrix after using fine ASIC gain settings for gain trimming.