Bob Blum (email@example.com)
The Ohio State InfraRed Imager/Spectrometer (OSIRIS) had its Rockwell HAWAII array replaced in December 1999. New parameters and performance information can be found in the OSIRIS web pages (http://www.ctio.noao.edu/instruments/ir_instruments/osiris). The new array is similar in most respects to the old, but does not exhibit the severe ramping at the quadrant boundaries that the old array did and appears to have a deeper full-well capacity.
OSIRIS is now the default IR imager/spectrometer at CTIO. Its combined imaging and spectroscopic modes allow CTIO to make fewer instrument changes over bright-time runs, an important consideration as we begin to prepare for the additional operational load of SOAR. Observers should propose to use OSIRIS instead of CIRIM or the IRS. The IRS may occasionally be scheduled for very highly rated science proposals that need long wavelength coverage (> 2.5 m) or high resolution (R > 5000). CIRIM may be scheduled if it is advantageous to have both IR imagers on two different telescopes at the same time.