The "advanced disk laser" — An onboard laser diagnostics system for drop tower experiments

We report about recent developments concerning the "Advanced Disk Laser" system, which is intended for use in combustion experiments under microgravity conditions at the drop tower "Bremen". Since the system will be integrated into a modified drop capsule it has to be a compact and efficient solid state laser which can withstand decelerations of up to 40 g. The existing laboratory set up was redesigned to fit into the capsule. Therefore, the system layout was split in three platforms for optical components (seed laser, regenerative amplifier and frequency conversion) and one additional platform for media supplies. Afterwards, a special developed ultra stable structure was equipped with newly designed mechanical and electro-optical components, which in part have already been tested in drop experiments. Access for alignments is possible via remote control of a number of motorized mechanical mounts. The three optical platforms build a vibration-insulated, dust-free laser capsule of their own inside the drop capsule and can be used both in the capsule and in a laboratory environment. The new laser system was already optically adjusted and tested in the laboratory and reached a pulse energy of 20 mJ, as was expected. An extensive evaluation period is going to follow and will be finished with a series of combustion experiments.