ESPRESSO Coudé-Train: complexities of a simultaneous optical feeding from the four VLT unit telescopes

Alexandre Cabral; Manuel Abreu; João Coelho; Ricardo Gomes; Manuel Monteiro; António Oliveira; Pedro Santos; Gerardo Ávila; Bernard-Alexis Delabre; Marco Riva; Paolo Di Marcantonio; Igor Coretti; Nuno C. Santos; Filippo Zerbi; Denis Mégevand

doi:10.1117/12.2055876

28 July 2014 ESPRESSO Coudé-Train: complexities of a simultaneous optical feeding from the four VLT unit telescopes

Alexandre Cabral, Manuel Abreu, João Coelho, Ricardo Gomes, Manuel Monteiro, António Oliveira, Pedro Santos, Gerardo Ávila, Bernard-Alexis Delabre, Marco Riva, Paolo Di Marcantonio, Igor Coretti, Nuno C. Santos, Filippo Zerbi, Denis Mégevand

Author Affiliations +

Proceedings Volume 9147, Ground-based and Airborne Instrumentation for Astronomy V; 91478Q (2014) https://doi.org/10.1117/12.2055876
Event: SPIE Astronomical Telescopes + Instrumentation, 2014, Montréal, Quebec, Canada

Abstract

ESPRESSO is a fibre-fed, cross-dispersed, high-resolution, echelle spectrograph. Being the first purpose of ESPRESSO to develop a competitive and innovative high-resolution spectrograph to fully exploit the VLT (Very Large Telescope), and allow new science, it is important to develop the VLT array concept bearing in mind the need to obtain the highest stability, while preserving its best efficiency. This high-resolution ultra-stable spectrograph will be installed in the VLT at the Combined Coudé Laboratory (CCL), fed by four Coudé Trains, which brings the light from the Nasmyth platforms of the four VLT Unit Telescopes to the CCL. ESPRESSO will combine the efficiency of modern echelle spectrograph with extreme radial-velocity precision. It will achieve a gain of two magnitudes with respect to its predecessor HARPS, and the instrumental radial-velocity precision will be improved to reach cm/s level. Thanks to its ability of combining incoherently the light of the 4 UTs, ESPRESSO will offer new possibilities in various fields of astronomy. The Coudé Train is composed of a set of prisms, mirrors and lenses to deliver a pupil and an image in the CCL, including an Atmospheric Dispersion Compensator. The use of mainly refractive optics, and Total Internal Reflection, has the advantage of the inherent higher throughput, especially in the blue region of the spectrum. In this paper, we present the design of the Coudé Train, the evolution of the concept towards the manufacturing phase, its main characteristics and performances, and detail its subsystems: optical, mechanical and control electronics and software.

Citation Download Citation

Alexandre Cabral, Manuel Abreu, João Coelho, Ricardo Gomes, Manuel Monteiro, António Oliveira, Pedro Santos, Gerardo Ávila, Bernard-Alexis Delabre, Marco Riva, Paolo Di Marcantonio, Igor Coretti, Nuno C. Santos, Filippo Zerbi, and Denis Mégevand "ESPRESSO Coudé-Train: complexities of a simultaneous optical feeding from the four VLT unit telescopes", Proc. SPIE 9147, Ground-based and Airborne Instrumentation for Astronomy V, 91478Q (28 July 2014); https://doi.org/10.1117/12.2055876

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

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.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available