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arXiv · 1208.0832

NIMBUS: The Near-Infrared Multi-Band Ultraprecise Spectroimager for SOFIA

Abstract

We present a new and innovative near-infrared multi-band ultraprecise spectroimager (NIMBUS) for SOFIA. This design is capable of characterizing a large sample of extrasolar planet atmospheres by measuring elemental and molecular abundances during primary transit and occultation. This wide-field spectroimager would also provide new insights into Trans-Neptunian Objects (TNO), Solar System occultations, brown dwarf atmospheres, carbon chemistry in globular clusters, chemical gradients in nearby galaxies, and galaxy photometric redshifts. NIMBUS would be the premier ultraprecise spectroimager by taking advantage of the SOFIA observatory and state of the art infrared technologies. This optical design splits the beam into eight separate spectral bandpasses, centered around key molecular bands from 1 to 4 microns. Each spectral channel has a wide field of view for simultaneous observations of a reference star that can decorrelate time-variable atmospheric and optical assembly effects, allowing the instrument to achieve ultraprecise calibration for imaging and photometry for a wide variety of astrophysical sources. NIMBUS produces the same data products as a low-resolution integral field spectrograph over a large spectral bandpass, but this design obviates many of the problems that preclude high-precision measurements with traditional slit and integral field spectrographs. This instrument concept is currently not funded for development.

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Michael W. McElwain, Avi Mandell, Bruce Woodgate, David S. Spiegel, Nikku Madhusudhan, Edward Amatucci, Cullen Blake, Jason Budinoff, Adam Burgasser, Adam Burrows, Mark Clampin, Charlie Conroy, L. Drake Deming, Edward Dunham, Roger Foltz, Qian Gong, Heather Knutson, Theodore Muench, Ruth Murray-Clay, Hume Peabody, Bernard Rauscher, Stephen A. Rinehart, Geronimo Villanueva. 2012-08-03. NIMBUS: The Near-Infrared Multi-Band Ultraprecise Spectroimager for SOFIA. https://doi.org/10.1117/12.927094

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