Goodman High Throughput Spectrograph

Updated Feb 3, 2017 (César Briceño)

NEW: the mask cutter at Gemini-S/CTIO is again operative. Users requesting the Goodman MOS mode can submit their mask files 1 month in advance of their observing run (see the MOS Slit Design Guide)

The Goodman High Throughput Spectrograph (GTHS) was built in the Goodman Laboratory at the University of North Carolina under the leadership of Prof. J. Christopher Clemens. It is an imaging spectrograph, capable of producing excellent image quality across a 7.2 arcmin diameter FOV (with a 0.15 arcsec/pixel scale), and spectra at various resolutions from the atmospheric UV cutoff all the way out to 850nm. It employs all transmissive optics, and Volume Phase Holographic (VPH) Gratings to achieve the highest possible throughput for low resolution spectroscopy over the 320-850 nm wavelength range.

Quick facts:

  • Scale: 0.15 arcsec/pixel
  • Wavelength range: 320 - 900 nm
  • Two Cameras (detectors) available:
    • Blue Camera: optimized for the UV, down to 320nm
    • Red Camera: best response redward of ~400nm with negligible fringing out to 900nm.
  • Imaging: circular 7.2 arcmin diameter field. 
    • SDSS, Bessell and Narrow-band filters (4x4 inch square). Up to 4 filters for imaging
  • Spectroscopy: single slit and Multi-Object Slit (MOS)
    • Single slits from 0.46 to 10 arcsec wide, 3.9 arcmin long.
    • Order sorting filters (always mounted)
    • Gratings from 400 to 2400 l/mm
  • MOS mode: masks span 3x5 arcmin rectangular field
  • Atmospheric Dispersion Corrector (ADC) available. The SOAR ADC is capable of full correction down to elevations of 30 deg above the horizon. Below that, and down to the 15 deg elevation limit of the telescope, the correction will be only partial; however, we recommend avoinding targets at elevations lower than 20 deg.  The ADC is most useful for MOS observations, or when the program does not allow orienting the slit at the paralactic angle.

General Information:

Observing Information and Tutorials:

Calibration Information:

Software for Goodman:

Data Reduction Guides:  coming soon!