The McMath-Pierce facility offers capabilities that are unique in the world for infrared solar observations: an unobstructed, all-reflecting light path (giving full access to wavelengths that the atmosphere transmits) and large aperture (for angular resolution and photon flux). These capabilities cannot be fully exploited without a state-of-the-art infrared array detector at the focal plane.
The present detector is a commercial 256 x 256 InSb array from Amber Engineering, re-housed in a dewar from Infrared Laboratories. This system was chosen for low initial cost and 1-5 µm wavelength coverage. It has served well---for example, observing for the first time the spatial structure of the Sun's cool carbon monoxide "COmosphere" but the camera is becoming obsolete.
NSO plans to replace the Amber array with a state-of-the-art 1-5 µm camera by taking advantage of NOAO's investment in the Aladdin array development project. The performance of an Aladdin-based system will surpass the current system in every important respect (dark current, readout noise, quantum efficiency, and immunity from electronic interference); its 15-20 Hz frame rate is well matched to the requirements of the infrared magnetographs (NIM and NIM-2).
NSO carried over FY 1996 funds into FY 1997 for an Aladdin controller to be constructed by the NOAO Instrument Projects Group. With the timely support of NOAO/IPG, funding was committed at the end of FY 1997 to purchase the hardware associated with the controller, including CPUs and A-to-Ds, I/O modules, power supplies, chassis, and enclosure. NSO expects to be ready by the end of FY 1998 to utilize a science-grade Aladdin array.
We thank Larry Daggert, Neil Gaughan and Richard Lund for their help in getting the requisitions out the door.
Lonnie Cole, Doug Rabin