Translator Disclaimer
Paper
7 July 2004 Performance analysis of the improved seeing limited mode for the Euro50
Author Affiliations +
Proceedings Volume 5382, Second Backaskog Workshop on Extremely Large Telescopes; (2004) https://doi.org/10.1117/12.566270
Event: Second Backaskog Workshop on Extremely Large Telescopes, 2003, Backaskog, Sweden
Abstract
This paper presents an analysis of the point-spread functions (PSFs), which may be expected in the so-called improved seeing limited mode for the Euro50 (Extremely large telescope with a 50 m aperture). This mode comprises adaptive control of the deformable secondary mirror of the aplanatic Gregorian telescope configuration using guide stars in a wide field. I may result in efficient compensation of turbulence-induced wavefront distortion near the ground layer. The prime goal of the investigations has been to evaluate the performance, in particular the full width at half maximum (FWHM) of the K-band PSFs, as a function of both the guide star field size and the outer scale of the atmospheric fluctuations. For this reason we have adopted a very simple guide star configuration consisting of a circular ring of homogeneously distributed stars. The PSFs are analyzed in the center of the ring. The atmosphere is implemented as the nine layer extended ORM atmosphere described in the paper. One result of the investigations is that the FWHM of the PSFs is very sesitive to the size of the outer scale. For a layer-common outer scale of 20 m, that is slightly less than half of the telescope diameter, the FWHM will stay close to the diffraction limit even for a guide star ring diameter of 10'. This makes the improved seeing limited mode very well suited for a fiber-fed spectrograph located at the F/5 Nasmyth focus of the Euro50.
© (2004) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Mette Owner-Petersen and Alexander V. Goncharov "Performance analysis of the improved seeing limited mode for the Euro50", Proc. SPIE 5382, Second Backaskog Workshop on Extremely Large Telescopes, (7 July 2004); https://doi.org/10.1117/12.566270
PROCEEDINGS
6 PAGES


SHARE
Advertisement
Advertisement
RELATED CONTENT


Back to Top