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An Optical Ultra-High-Resolution Cross-dispersed Echelle Spectrograph with Adaptive Optics

Jian Ge·J. R. P. Angel·B. Jacobsen·N. Woolf·R. Q. Fugate·J. H. Black
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Abstract

A prototype cross-dispersed optical echelle spectrograph of very high resolution has been designed and built at Steward Observatory and tested at the Starfire Optical Range (SOR) 1.5 m telescope. It is the first spectrograph to take advantage of diffraction-limited images provided by adaptive optics in order to achieve a potential resolving power of $R \sim 600,000$. The wavelength coverage in a single exposure is about 300 Å, which is approximately 100 times that of conventional spectrographs operating at comparable resolution. This was achieved by recording 60 cross-dispersed orders across the $18\times 18$ mm$^2$ area of the CCD detector. The total efficiency of the system, including the sky and telescope transmission, spectrograph and CCD detector, is measured to be 1.3% at peak, much higher than that of other ultra-high-resolution spectrographs. Sample stellar spectra with $R \sim 250,000$ are presented.

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Jian Ge, J. R. P. Angel, B. Jacobsen, N. Woolf, R. Q. Fugate, J. H. Black. 2002-04-26. An Optical Ultra-High-Resolution Cross-dispersed Echelle Spectrograph with Adaptive Optics. https://doi.org/10.1086/341711

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