GNIRS was built by NOAO in Tucson, Arizona and delivered to Cerro Pachon in late October 2003; an Integral Field Unit (IFU) built by the University of Durham was integrated into the instrument early in 2004. Commissioning of the majority of the modes took place in stages during 2004.  GNIRS was first made available for science use in 2004B. The instrument was damaged in 2007 while at Cerro Pachon is now being repaired and readied for use at Mauna Kea.

GNIRS offers a wide variety of spectroscopic capabilities including long-slit (single order) spectroscopy within the 1-5.5 µm range at 2-pixel spectral resolutions of approx 1700, 5900 and 18000 with a choice of 2 pixel scales (0.15"/pix and 0.05"/pix), and cross-dispersed spectroscopy giving complete 1-2.5 µm coverage at R~1700 and partial coverage at 5900. The different pixel scales are achieved with four cold-changeable cameras of "long" and "short" focal lengths optimized for "blue" (1-2.5 µm) and "red" (3-5 µm) wavelengths.

The Instrument Scientist for GNIRS is Tom Geballe.

Announcements

In April 2007, GNIRS was damaged by overheating during a routine warmup. It is currently undergoing repairs and is not offered for science in the 2008 semesters - see GNIRS Recovery - for more details. It is expected that GNIRS will be re-commissioned on Gemini North in Semester 2009A and will return to normal operations in Semester 2009B .

See the Status and Availability pages for archived news items.

GNIRS science highlights

How to use these pages

The GNIRS pages are organized as follows.

• Status and Availability: Modes available in the current and upcoming semesters
• Long-Slit, Cross-Dispersed and IFU Spectroscopy: Characteristics of GNIRS' various spectroscopic modes and guidelines on how best to use the instrument in these modes.
• Sensitivity and Overheads: Sensitivity tables, integration time calculator, and details of observing overheads
• Guiding Options: Guiding considerations, and wavefront sensors available for use with GNIRS
• Calibration: Info on GCAL, flats and arcs, standard stars, and baseline calibrations
• Observation Preparation: How to configure GNIRS in the Observing Tool
• Data Format and Reduction: Examples of GNIRS data and links to data reduction resources
• Documents: GNIRS optical layout; design documents and references

Also see the Near-IR Resources section, which contains generic information about observing at 1-5 µm as well as details about calibrations, standard stars, etc. that apply to NIRI, GNIRS, NIFS, Phoenix and FLAMINGOS-2.

Click on the image to see a close-up view of GNIRS on Gemini South