A. Cabral, M. Aliverti, J. Coelho, M. Abreu, M. Riva, A. Marconi, L. Valenziano, E. Oliva

Abstract
HIRES is a high-resolution spectrograph to me mounted on one of the Nasmyth foci of the ESO Extremely Large Telescope in Chile. This instrument will be composed by up to four Spectrograph to cover a high spectral range: one for the U band, one for the BVRI band, one for the ZYJH band, and one for the K band. To stabilize and inject the light coming from the telescope into the different spectrographs a Front End will be installed on the Nasmyth focus. In this paper, the design of the HIRES Front End will be presented. It will be composed by a structure, a cable derotator and four benches: two for the Observation mode, one for the Polarimeter arm, and one for the IFU/SCAO. Due to the absence of an interface flange with the telescope the cable derotator will directly support the four benches, positioning them in operation or standby mode. Moreover, due to the different requirements, the cables bundles will be split and derotated in different ways: part of them using different wheels, part of them twisting the cables. For the most critical ones, the electronic will be directly integrated on the derotator system. The preliminary optical and optomechanical design of the observing mode arm will be detailed also showing the techniques used to maximize the modularity of the four sub-Front End modules in order to decrease the Mean Time To Repair and allow for future upgrades or modifications on the single bands.

Ground-based and Airborne Instrumentation for Astronomy VII
Christopher J. Evans, Luc Simard, Hideki Takami

SPIE
Proceedings of the SPIE
Volume 10702
2018 July

>> DOI