User's Guide to the Gemini Twin-Arrays Infrared Camera

Table of Contents

Quick Reference
What is Gemini?
Summary Table
Quick start - for the expert
Not so quick start - set-up
Graphical User Interface
More About Gemini
Signal-to-Noise Estimates
Sampling Modes
Writing Scripts
Observing Recipes
Computer Setup
Testing the Arrays
Instrument Maintenance and Trouble-Shooting

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The performance of Gemini (prior to June 1994) is described in the SPIE Kona conference paper (McLean et al. 1994). Several improvements were made after than meeting which led to improved performance at wavelengths longer than 3 um. The following tables give the current estimates or measurements of important properties.

Typical measured point source sensitivities on the 3-m telescope
Filter/Band (um)B (e-/s/pix) B (mag/arcsec2)mZP %mlim, 3-sigma, 1 min tFWtblip
J (1.22, 0.29)120016.121.4 1919.0167 s2.1 s
H (1.63, 0.29)500014.321.2 3317.840 s0.5 s
K (2.1, 0.35)1010013.020.5 3417.215 s0.4 s
nbL (3.6, 0.07)2.5 x 106 4.816.5 271260 ms1.4 ms
NB: Add 2.2 magnitudes to mlim for 3-sigma, 1 hour.

Measured Detector Properties
Rockwell HgCdTe (NICMOS 3)SBRC InSb
Full Well200,000 electrons 150,000 electrons
Q.E. (J)40 %---
Q.E. (H)60 %---
Q.E. (K)60 %70 %
Q.E. (L)---70 %
Mean Dark Current< 1 e-/s/pixel < 15 e-/s/pixel
Non-uniformity10 %5 %
Good Pixels99.6 %99.9 %
Noise in 8 reads (Fowler CDS)30 electons 40 electrons

Last modified: Mon Apr 21 04:05:01 PDT 2008 by Elinor Gates