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arXiv · 2301.08048

CRIRES$^{+}$ on sky at the ESO Very Large Telescope

R. J. Dorn·P. Bristow·J. V. Smoker·F. Rodler·A. Lavail·M. Accardo·M. van den Ancker·D. Baade·A. Baruffolo·B. Courtney-Barrer·L. Blanco·A. Brucalassi·C. Cumani·R. Follert·A. Haimerl·A. Hatzes·M. Haug·U. Heiter·R. Hinterschuster·N. Hubin·D. J. Ives·Y. Jung·M. Jones·J-P. Kirchbauer·B. Klein·O. Kochukhov·H. H. Korhonen·J. Köhler·J-L. Lizon·C. Moins·I. Molina-Conde·T. Marquart·M. Neeser·E. Oliva·L. Pallanca·L. Pasquini·J. Paufique·N. Piskunov·A. Reiners·D. Schneller·R. Schmutzer·U. Seemann·D. Slumstrup·A. Smette·J. Stegmeier·E. Stempels·S. Tordo·E. Valenti·J. J. Valenzuela·J. Vernet·J. Vinther·A. Wehrhahn
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Abstract

The CRyogenic InfraRed Echelle Spectrograph (CRIRES) Upgrade project CRIRES$^{+}$ extended the capabilities of CRIRES. It transformed this VLT instrument into a cross-dispersed spectrograph to increase the wavelength range that is covered simultaneously by up to a factor of ten. In addition, a new detector focal plane array of three Hawaii 2RG detectors with a 5.3 $\mu$m cutoff wavelength replaced the existing detectors. Amongst many other improvements, a new spectropolarimetric unit was added and the calibration system has been enhanced. The instrument was installed at the VLT on Unit Telescope 3 at the beginning of 2020 and successfully commissioned and verified for science operations during 2021, partly remotely from Europe due to the COVID-19 pandemic. The instrument was subsequently offered to the community from October 2021 onwards. This article describes the performance and capabilities of the upgraded instrument and presents on sky results.

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R. J. Dorn, P. Bristow, J. V. Smoker, F. Rodler, A. Lavail, M. Accardo, M. van den Ancker, D. Baade, A. Baruffolo, B. Courtney-Barrer, L. Blanco, A. Brucalassi, C. Cumani, R. Follert, A. Haimerl, A. Hatzes, M. Haug, U. Heiter, R. Hinterschuster, N. Hubin, D. J. Ives, Y. Jung, M. Jones, J-P. Kirchbauer, B. Klein, O. Kochukhov, H. H. Korhonen, J. Köhler, J-L. Lizon, C. Moins, I. Molina-Conde, T. Marquart, M. Neeser, E. Oliva, L. Pallanca, L. Pasquini, J. Paufique, N. Piskunov, A. Reiners, D. Schneller, R. Schmutzer, U. Seemann, D. Slumstrup, A. Smette, J. Stegmeier, E. Stempels, S. Tordo, E. Valenti, J. J. Valenzuela, J. Vernet, J. Vinther, A. Wehrhahn. 2023-01-19. CRIRES$^{+}$ on sky at the ESO Very Large Telescope. https://doi.org/10.1051/0004-6361/202245217

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