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

Mt. Hamilton Homepage

Summary Table

Image scale:0.68" per pixel
Field of View:174" x 174"
Features: Twin IR arrays + dichroic beam-splitters
Channel A: Short Wave - NICMOS3 256x256 pixels HgCdTe
Channel B: Long Wave - SBRC 256x256 pixels InSb
Dichroics: K band to SW channel
K band to LW channel
TELCO control for mosaics using SCRIPTS
External Polarimeter: In/Out, Rotatable Halfwave Plate (22.5 degree steps)
Aperture Wheel: Open, 5" Occulting Spot, 120" Long Slit, Short Double Slits
Auxiliary Aperture Wheel: Open, Polarizer, Calcite Cube
Filter Wheels: 10 positions
Channel A (SW) Channel B (LW)
Blank (dark)Blank (dark)
H grismK grism
Paschen BetaH2
1.3095Brackett Gamma
He IK continuum
He continuumCO
J grismHe II
J3.15 continuum
KK' [NB: Filters last changed 11 Mar 1999.]
Modes: Imaging, Spectroscopy (R=500), Polarimetry
Throughput: about 30% (less at J band)
Noise:1 - 3 DN depending on readout mode (CDS, Fowler, Multiple Converts)
Gain: Channel A: 19 electrons/DN
Channel B: 24 electrons/DN
Backgrounds: J = 16.0 mag per square arcsec
H = 14.0 mag per square arcsec
K = 13.0 mag per square arcsec
Zeropoints (1 DN/s): J = 21.4
H = 20.9
K = 20.4

Last modified: Tue Jun 17 22:51:14 PDT 2008 by Elinor Gates