You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither SPIE nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the SPIE website.
22 July 2014Turkey's next big science project: DAG the 4 meter telescope
The DAG (Turkish for Eastern Anatolia Observatory) 4-m telescope project has been formally launched in
2012, being fully funded by the Government of Turkey. This new observatory is to be located on a 3170 m
altitude ridge near the town of Erzurum in Eastern Anatolia. First light is scheduled for late 2017. The
DAG team’s baseline design of the telescope consists of a Ritchey-Chretien type with alt-az mount, a focal
length of 56 m and a field of view up to 30 arcmin. Multiple instruments will be located at the Nasmyth
foci. The optical specifications of the telescope are set by DAG team for diffraction limited performance
with active and adaptive optics. Modern mirror control technologies will allow defining in a most cost
effective way the figuring requirements of the optical surfaces: the low order figuring errors of the
combined optical train constituted of M1-M2-M3 are defined in terms of Zernike coefficients and referred
to the M1 surface area. The high order figuring errors are defined using the phase structure functions.
Daytime chilling of the closed enclosure volume and natural ventilation through suitable openings during
observations will be used to ensure optimal mirror and dome seeing. A design of a ground layer adaptive
optics (GLAO) subsystem is developed concurrently with the telescope. In this paper, main design aspects,
the optical design and expected performance analysis of the telescope will be presented.
The alert did not successfully save. Please try again later.
O. Keskin, C. Yesilyaprak, S. K. Yerli, L. Zago, L. Jolissaint, "Turkey's next big science project: DAG the 4 meter telescope," Proc. SPIE 9145, Ground-based and Airborne Telescopes V, 914547 (22 July 2014); https://doi.org/10.1117/12.2067599