OAJ: 2.6m wide field survey telescope

Abstract

AMOS S.A. is in charge of the development of the telescopes for the "Observatorio Astrofisico de Javalambre" in Spain where a 2.6 m wide field telescope is complemented by an 80 cm telescope. This paper focuses on the 2.6 m telescope Javalambre Survey Telescope (JST): it is combining a large collecting surface with a wide field of view for reaching a vast portion of the sky, which is the most relevant parameter for surveys, while ensuring an optical image quality compatible with the site seeing and a suitable depth in the sky sighting. The major difficulty consists in maintaining the image quality over a 500 mm focal plane. A good design is the result of a thorough multidisciplinary optimization process where the fabrication constraints are a major driving parameter. The complexity of the system led to elaborate innovative solutions for the closed loop control of both image quality and tracking features. The design and the methodology of working are presented in details. The optics fabrication, the integration and acceptance tests are also reviewed.