Cunningham, Mark;
Doel, Peter;
Brooks, David;
Brynnel, Joar;
De Jongb, Roelof;
Frey, Steffen;
Schroeck, Michael;
... Barden, Sam C; + view all
(2022)
The assembly and alignment of the 4MOST Wide Field Corrector.
In: Evans, CJ and Bryant, JJ and Motohara, K, (eds.)
Proceedings of SPIE: Ground-based and Airborne Instrumentation for Astronomy IX.
(pp. pp. 1-18).
Society of Photo-Optical Instrumentation Engineers (SPIE)
Preview |
Text
121846V.pdf - Published Version Download (61MB) | Preview |
Abstract
The 4-metre Multi-Object Spectroscopic Telescope (4MOST) is a fibre-fed multi-object spectrograph for the VISTA telescope at the ESO Paranal Observatory in Chile. The goal of the 4MOST project is to create a general-purpose and highly efficient spectroscopic survey facility for astronomers in the 4MOST consortium and the ESO community. The instrument itself will record 2436 simultaneous spectra over a ∼4.2 square degree field of view and consists of an optical Wide-Field Corrector (WFC), a fibre positioner system based on a tilting spine design, and three spectrographs giving both high and low spectral dispersion. The WFC comprises of 6 lenses grouped into 4 elements, 2 of which are cemented doublets that act as an atmospheric dispersion corrector (ADC). The first lens element is 0.9m in diameter whilst the diameter of the other elements is 0.65m. For the instrument to meet its science goals, each lens needs to be aligned to ∼50µm – a major challenge. This is achieved using contact metrology methods supplemented by pencil beam laser probes. In particular, a novel off-axis laser beam system has been implemented to test the optics’ alignment before and after shipment. This paper details the alignment and assembly methods and presents the latest results on the achieved lens positioning and projected performance of the WFC
| Type: | Proceedings paper |
|---|---|
| Title: | The assembly and alignment of the 4MOST Wide Field Corrector |
| Event: | Conference on Ground-Based and Airborne Instrumentation for Astronomy IX |
| Location: | Montreal, QC, Canada |
| Dates: | 17th-22nd July 2022 |
| ISBN-13: | 978-1-5106-5349-8 |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1117/12.2629247 |
| Publisher version: | https://doi.org/10.1117/12.2629247 |
| Language: | English |
| Additional information: | This version is the version of record. For information on re-use, please refer to the publisher's terms and conditions. |
| Keywords: | Wide-field multi-object spectrograph facility, VISTA telescope, Wide Field Corrector, 4MOST |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy |
| URI: | https://discovery-pp.ucl.ac.uk/id/eprint/10158920 |
Archive Staff Only
 |
View Item |
