GNIRS

Observing Modes:

Three main observing modes are possible with the instrument as configured at Gemini North — long slit spectroscopy, cross dispersed spectroscopy, and imaging. The instrument design and use are discussed on the GNIRS web page.

System Verification:

In 2010 the Gemini observatory called for System Verification proposals for GNIRS. The resulting data is public and is a good source of material to test data reduction procedures. Further details and links to the data packets are available here.

Data Reduction:

Data reduction of GNIRS spectra was one of the first tasks of Gemini IRAF. A paper by A. Cooke and B. Rodgers (2005, in “Astronomical Data Analysis Software and Systems XIV”, ASP Conf. Series 347, P.L. Shopbell, M.C. Britton, R. Ebert, eds., 514) discusses reducing all types of spectroscopy data from GNIRS using Gemini IRAF tasks. This is a mini-cook book with each task discussed. There are also independently prepared cookbooks for both long slit and cross dispersed spectroscopy available on the getting-started page. A general discussion of GNIRS data reduction can be found in a presentation by Rachel Mason that was given at the South American Gemini Data Workshop.   

The Gemini GNIRS web site under Data Format and Reduction points to the Gemini IRAF package link. The two major points discussed here are removing electronic pattern noise using CLEANIR and reducing XD spectra.

For XD spectra there is also a pipe line/cookbook written by R. Mason. A discussion and examples are provided here. The data and reduction commands be found at the Gemini Data Reduction User Forum.

Last updated or reviewed January 19, 2017.