Design Options for High-Performance High-Resolution Near-Infrared Spectrographs

摘要

The combination of immersion grating and infrared array detector technologies now allows the construction of high-resolution spectrographs in the near-infrared that have capabilities approaching those of optical spectrographs. It is possible, for instance, to design multi-object spectrographs with very large wavelength coverage and high throughput. However, infrared spectrographs must be cryogenic and the cost of complexity can be large. We investigate lower cost design options for single-object high-resolution spectrographs. The trade-off in these designs is between the sizeumber of infrared arrays and the inclusion of moving parts. We present a design for a no moving parts spectrograph with either 1.1-2.5 or 3-5 μm simultaneous wavelength coverage. The design was undertaken with attention to cost as well as scientific merit. Here we review the science drivers and key functional requirements. We present a general overview of the instrument and estimate the limiting performance. The performance is compared with that of medium-resolution infrared spectrographs as well as other high-resolution infrared spectrographs.