The European Solar Telescope (EST) is a 4-meter class solar telescope led by the Instituto Astrofísico de Canarias that will be erected in La Palma Island. The design process is now approaching the Preliminary Design Review. The EST, as solar telescope, will have singularities that make its design differ from other telescopes. Telescope configuration, high solar radiation, absence of dome during observation, besides other elements, will have a strongly impact to the system design. One of the telescope critical elements is the primary mirror and its support. Along the last months, the preliminary design of these items has been performed. Critical aspects as mirror heat rejection, surface temperature and homogeneity, shape error, wind perturbations, etc., have had strong influence in the design solutions, pushing to use, for example, the thinner solid meniscus mirror never manufactured supported by 80 tripods over electromechanical actuators. This paper presents the design of the primary mirror and its support, presenting the adopted design solutions to cope with the different difficulties as well as the results of some protypes manufactured to reduce the project risk.
The European Solar Telescope (EST) is a 4-m class solar telescope that will be installed at the Observatorio del Roque de los Muchachos in La Palma (Spain). Two important factors make EST different from other similar size telescopes: high thermal load due to solar radiation and open dome configuration during observation. Therefore, the entire telescope will be exposed to direct and indirect solar radiation, which requires a very demanding thermal management in order to minimize local seeing. In addition, the complete telescope will be exposed to wind, which has an important impact both in image stability and image quality. The EST M1 Assembly (primary mirror and cell) will have to cope with these critical issues, apart from other aspects common to primary mirrors of similar size. In 2020, in the scope of the EST Preliminary Design Phase, the development of the M1 Assembly was granted to the company SENER-Aeroespacial. The first step, before starting the design, was to evaluate different technologies and configurations for the following critical aspects: mirror (lightweight or not), number and type of axial actuators, cooling system, and number of interfaces with the elevation tube. A comparative study was carried out in order to define the baseline configuration for the M1 Assembly. This baseline configuration was then fully developed up to preliminary design level. This paper addresses the comparative study performed for selecting the most promising baseline configuration for the EST M1 Assembly.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.