Overview

IGRINS (Immersion GRating INfrared Spectrometer) is a compact high-resolution near-infrared spectrograph that primarily disperses light with a silicon immersion grating. Individual volume phase holographic (VPH) gratings serve as cross-dispersing elements for separate spectrograph arms covering the H and K bands. IGRINS observations cover the entire wavelength range between 1.45 and 2.45μm, and do so in a single exposure with a resolving power of R~45,000. As there are no moving cryogenic parts, all observations have the same spectral format (Yuk et al. 2010, Park et al. 2014, Mace et al. 2016, Mace et al. 2018). 

Since commissioning in July 2014, IGRINS has been scheduled for more that 1000 nights on the 2.7m Harlan J. Smith Telescope at McDonald Observatory, the 4.3m Discovery Channel Telescope at Lowell Observatory, and the 8.1m Gemini South telescope.

IGRINS returned to the Gemini South telescope as a long-term visiting instrument in February 2020 and departed in April 2024. 

At Gemini, the slit size is 0.34ʺ x 5ʺ. The plate scale on the imaging detector is ~0.041"/pix, and ~0.091"/pix in the spatial direction of the 2-D spectrum. Optimal targets will be those with K-band magnitudes between 10-14, but objects between K=4 and 16 mags are possible. A python based data reduction pipeline for IGRINS is available to the public and there is a large IGRINS user community available for collaboration. 

IGRINS is no longer available at Gemini South. It will return to McDonald Observatory in late 2024.

The Raw and Reduced IGRINS Spectral Archive (RRISA) contains non-proprietary IGRINS data.

IGRINS-2 is being commissioned on Gemini North and will be available in future semesters there.