4 papers
Simultaneous Measurements of the Fried Parameter r_0 and the Isoplanatic Angle theta_0 using SCIDAR and Adaptive Optics - First Results
A. R. Weiss, S. Hippler, M. E. Kasper +2
We present first results of a simultaneous atmospheric turbulence measurement campaign at the Calar Alto (Spain) 1.23m and 3.5m telescopes. A SCIDAR instrument and the Calar Alto A…
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…
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…