CorMass - Quick Information and Specifications

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This page last updated: July 6, 2006 - JMD
This page last checked: September 26, 2004 - JMD

Information in Yellow may not be correct or is missing for this instrument!!!

Brief Instrument Description

CorMASS (Cornell Massachusetts Slit Spectrograph) is a low-resolution (R~300) prism cross-dispersed NIR Spectrograph. It has been used on the Palomar Observatory 60-inch telescope, the Vatican Observatory 1.8-meter telescope, and the Magellan 6.5-meter telescope but resides at APO until further notice. CorMASS' 2-dimensional spectral format provides simultaneous coverage of the IJHK bands, from ~0.75 microns to 2.5 microns. A remotely operated flip mirror allows the use of a slit viewing mode for object placement on the 5.5 x 0.75 arcsecond slit. CorMASS science includes rapid classification of brown dwarfs, determining redshifts of heavily reddened AGN, Wolf-Rayet star spectroscopy, examining temporal variation of T Tauri star absorption and emission lines, carbon star spectroscopy, novae spectroscopy, characterization of ices on outer solar-system icy satellites, and has obtained an integrated spectrum of Earth from lunar reflected earthshine. Also available is Cormasstool, a spectral reduction widget- based IDL package modified from Spextool, written by Mike Cushing and Bill Vacca.

CorMass Quick  Information

• CCD is a NICMOS3 256x256 CCD
• CCD pixel size = 40µm pixels
• CCD gain = 8.5 e^-/ADU
• CCD read noise = 43 e^-
• Quantum Effeciency ~70%
• Dark Current: <1 e- / second
• Pixel scale = 0.375"/pixel in slit mode, 0.105"/pixel in slit view mode
• Full well depth: 300k e^-
• Saturation is at 40k, therefore try to keep counts < 20k
• Installed filters (User selectable):
• Available gratings (Observing Specialist installable):
• Resolution: R ~ 300
• Spectral Coverage: 0.6-2.5 micron (although efficiency is poor shortward of 0.75 micron)
• Field of View: 0.75" x 5.7" in slit mode, 10" in slit view mode
• Ks filter (slit viewer)
• Minimum Exposure time: 0.7s
• Readout Time: 1.4s