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arXiv · 2207.14143

NIRPS Front-End: Design, performance, and lessons learned

N. Blind·U. Conod·A. de Meideros·F. Wildi·F. Bouchy·S. Bovay·D. Brousseau·A. Cabral·L. Genolet·J. Kolb·R. Schnell·A. Segovia·M. Sordet·S. Thibault·B. Wehbe·G. Zins
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Abstract

NIRPS (Near Infra-Red Planet Searcher) is an AO-assisted and fiber-fed spectrograph for high precision radial velocity measurements in the YJH-bands. NIRPS also has the specificity to be an SCAO assisted instrument, enabling the use of few-mode fibers for the first time. This choice offers an excellent trade-off by allowing to design a compact cryogenic spectrograph, while maintaining a high coupling efficiency under bad seeing conditions and for faint stars. The main drawback resides in a much more important modal-noise, a problem that has to be tackled for allowing 1m/s precision radial velocity measurements. In this paper, we present the NIRPS Front-End: an overview of its design (opto-mechanics, control), its performance on-sky, as well as a few lessons learned along the way.

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N. Blind, U. Conod, A. de Meideros, F. Wildi, F. Bouchy, S. Bovay, D. Brousseau, A. Cabral, L. Genolet, J. Kolb, R. Schnell, A. Segovia, M. Sordet, S. Thibault, B. Wehbe, G. Zins. 2022-07-28. NIRPS Front-End: Design, performance, and lessons learned. https://arxiv.org/abs/2207.14143

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