ALFA: First Operational Experience of the MPE/MPIA Laser Guide Star   System for Adaptive Optics
  The sodium laser guide star adaptive optics system ALFA has been constructed at the Calar Alto 3.5-m telescope. Following the first detection of the laser beacon on the wavefront sensor in 1997 the system is now being optimized for best performance. In this contribution we discuss the current status of the launch beam and the planned improvements and upgrades. We report on the performance level achieved when it is used with the adaptive optics system, and relate various aspects of our experience during operation of the system. We have begun to produce scientific results and mention two of these. 
R. I. Davies, W. Hackenberg, T. Ott, A. Eckart, H.-C. Holstenberg, S.   Rabien, A. Quirrenbach, M. Kasper