5 papers · 1 filter
Near-infrared adaptive optics observations of galaxy clusters: Abell 262 at z=0.0157, J1836.3CR at z=0.414, and PKS 0743-006 at z=0.994
W. Hackenberg, A. Eckart, R. I. Davies +5
We report on high angular resolution near-infrared (NIR) observations of three galaxy clusters at different redshifts using adaptive optics (AO). In the case of the barred spiral \…
The ALFA Laser: Beam Relay and Control System
T. Ott, W. Hackenberg, S. Rabien +2
The ALFA laser subsystem uses a 4 watt continuous wave laser beam to produce an artificial guide star in the mesospheric sodium layer as a reference for wavefront sensing. In this…
The ALFA Laser and Analysis Tools
S. Rabien, T. Ott, W. Hackenberg +4
The optimal performance of adaptive optics systems can only be maintained if the wavefront reference is bright and compact. Experience has shown that both of these important criter…
The ALFA laser guide star: Operation and Results
R. Davies, A. Eckart, W. Hackenberg +4
The importance of laser guide stars to the practical usefulness of adaptive optics cannot be understated, and yet there are very few working systems. This contribution discusses th…
First Observational Results from ALFA with Natural and Laser Guide Stars
R. I. Davies, W. Hackenberg, T. Ott +5
The sodium laser guide star adaptive optics system ALFA, which is installed at the Calar Alto 3.5-m telescope, has been undergoing an intensive optimisation phase. Observations usi…