The Near-Infrared Spectrograph (NIRSpec) on the<i>James Webb</i>Space Telescope
Torsten Böker, Santiago Arribas, Nora Lützgendorf, Catarina Alves de Oliveira, Tracy L. Beck, Stephan M. Birkmann, Andrew J. Bunker, S. Charlot, Guido De Marchi, Pierre Ferruit, Giovanna Giardino, P. Jakobsen, Nimisha Kumari, M. López-Caniego, R. Maiolino, Elena Manjavacas, A. P. Marston, S. H. Moseley, James Muzerolle, P. Ogle, Nor Pirzkal, Bernard J. Rauscher, Tim Rawle, Hans‐Walter Rix, Elena Sabbi, B. A. Sargent, M. Sirianni, Maurice te Plate, Jeff A. Valenti, Chris J. Willott, Peter Zeidler
Abstract
The near-infrared spectrograph (NIRSpec) on the James Webb Space Telescope (JWST) offers the first opportunity to use integral-field spectroscopy from space at near-infrared wavelengths. More specifically, NIRSpec’s integral-field unit can obtain spectra covering the wavelength range 0.6−5.3 μm for a contiguous 3.1″ × 3.2″ sky area at spectral resolutions of R ≈ 100, 1000, and 2700. In this paper we describe the optical and mechanical design of the NIRSpec integral-field spectroscopy mode, together with its expected performance. We also discuss a few recommended observing strategies, some of which are driven by the fact that NIRSpec is a multipurpose instrument with a number of different observing modes, which are discussed in companion papers. We briefly discuss the data processing steps required to produce wavelength- and flux-calibrated data cubes that contain the spatial and spectral information. Lastly, we mention a few scientific topics that are bound to benefit from this highly innovative capability offered by JWST/NIRSpec.