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arXiv · 2506.08378

Euclid preparation: The NISP spectroscopy channel, on ground performance and calibration

Euclid Collaboration·W. Gillard·T. Maciaszek·E. Prieto·F. Grupp·A. Costille·K. Jahnke·J. Clemens·S. Dusini·M. Carle·C. Sirignano·E. Medinaceli·S. Ligori·E. Franceschi·M. Trifoglio·W. Bon·R. Barbier·S. Ferriol·A. Secroun·N. Auricchio·P. Battaglia·C. Bonoli·L. Corcione·F. Hormuth·D. Le Mignant·G. Morgante·C. Padilla·R. Toledo-Moreo·L. Valenziano·R. Bender·F. J. Castander·P. B. Lilje·A. Balestra·J. -J. C. Barriere·M. Berthe·C. Boderndorf·A. Bonnefoi·V. Capobianco·R. Casas·H. Cho·F. Ducret·J. -L. Gimenez·W. Holmes·A. Hornstrup·M. Jhabvala·E. Jullo·R. Kohley·B. Kubik·R. Laureijs·I. Lloro·C. Macabiau·Y. Mellier·G. Polenta·G. D. Racca·A. Renzi·M. Schirmer·G. Seidel·M. Seiffert·G. Sirri·G. Smadja·L. Stanco·S. Wachter·H. Aussel·T. Auphan·B. R. Granett·R. Chary·Y. Copin·P. Hudelot·V. Le Brun·F. Torradeflot·P. N. Appleton·P. Casenove·P. -Y. Chabaud·M. Frailis·M. Fumana·L. Guzzo·G. Mainetti·D. Maino·M. Moresco·W. J. Percival·R. Scaramella·M. Scodeggio·N. R. Stickley·D. Vibert·Y. Wang·J. Zoubian·N. Aghanim·B. Altieri·A. Amara·S. Andreon·C. Baccigalupi·M. Baldi·S. Bardelli·A. Biviano·A. Bonchi·E. Branchini·M. Brescia·J. Brinchmann·S. Camera·G. Cañas-Herrera
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Abstract

ESA's Euclid cosmology mission relies on the very sensitive and accurately calibrated spectroscopy channel of the Near-Infrared Spectrometer and Photometer (NISP). With three operational grisms in two wavelength intervals, NISP provides diffraction-limited slitless spectroscopy over a field of $0.57$ deg$^2$. A blue grism $\text{BG}_\text{E}$ covers the wavelength range $926$--$1366$\,nm at a spectral resolution $R=440$--$900$ for a $0.5''$ diameter source with a dispersion of $1.24$ nm px$^{-1}$. Two red grisms $\text{RG}_\text{E}$ span $1206$ to $1892$\,nm at $R=550$--$740$ and a dispersion of $1.37$ nm px$^{-1}$. We describe the construction of the grisms as well as the ground testing of the flight model of the NISP instrument where these properties were established.

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Euclid Collaboration, W. Gillard, T. Maciaszek, E. Prieto, F. Grupp, A. Costille, K. Jahnke, J. Clemens, S. Dusini, M. Carle, C. Sirignano, E. Medinaceli, S. Ligori, E. Franceschi, M. Trifoglio, W. Bon, R. Barbier, S. Ferriol, A. Secroun, N. Auricchio, P. Battaglia, C. Bonoli, L. Corcione, F. Hormuth, D. Le Mignant, G. Morgante, C. Padilla, R. Toledo-Moreo, L. Valenziano, R. Bender, F. J. Castander, P. B. Lilje, A. Balestra, J. -J. C. Barriere, M. Berthe, C. Boderndorf, A. Bonnefoi, V. Capobianco, R. Casas, H. Cho, F. Ducret, J. -L. Gimenez, W. Holmes, A. Hornstrup, M. Jhabvala, E. Jullo, R. Kohley, B. Kubik, R. Laureijs, I. Lloro, C. Macabiau, Y. Mellier, G. Polenta, G. D. Racca, A. Renzi, M. Schirmer, G. Seidel, M. Seiffert, G. Sirri, G. Smadja, L. Stanco, S. Wachter, H. Aussel, T. Auphan, B. R. Granett, R. Chary, Y. Copin, P. Hudelot, V. Le Brun, F. Torradeflot, P. N. Appleton, P. Casenove, P. -Y. Chabaud, M. Frailis, M. Fumana, L. Guzzo, G. Mainetti, D. Maino, M. Moresco, W. J. Percival, R. Scaramella, M. Scodeggio, N. R. Stickley, D. Vibert, Y. Wang, J. Zoubian, N. Aghanim, B. Altieri, A. Amara, S. Andreon, C. Baccigalupi, M. Baldi, S. Bardelli, A. Biviano, A. Bonchi, E. Branchini, M. Brescia, J. Brinchmann, S. Camera, G. Cañas-Herrera. 2025-06-10. Euclid preparation: The NISP spectroscopy channel, on ground performance and calibration. https://doi.org/10.1051/0004-6361%2F202555859

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