Phase II of the cryostat fabrication (all the mechanical components required for the initial cryogenic tests - trusses, cold mounting structure, liquid nitrogen can, actively cooled radiation shield) was completed and delivered by Hughes Tools, in April. An investigation of the electrical power and a/c demands required to run the compressors for the cryostat and lab test dewar closed-cycle coolers concluded that both could not be run simultaneously in the IR Lab in Manoa. Approval was obtained to house the compressors in a separate room next to the lab and to upgrade the power supply to this room. Modifications to this room should be completed during next quarter. Work on these plans and continued fabrication and testing of the array controllers slowed assembly of Phase II.
During the quarter news was received that NSF had decided to fund the proposal, submitted in August 1997, for adding a high-speed low-resolution spectroscopy mode to SpeX. Funding was at the requested amount of $97k and the start date is July 1 1998.
In June, orders were placed for diffraction gratings, prisms and dichroic beam-splitters. Four plane reflection gratings were ordered from Carl Zeiss, Jena. Optics For Research were contracted to fabricate four cross-dispersing prisms and one dispersing prism. Thin Film Labs were contracted to make dichroic coatings, two with 0.8 micron cut-offs and two with 1.0 micron cut-offs, for use in both SpeX and NSFCAM.
In May, additional funds were approved to process the surplus InSb die. NASA HQ approved $90k to procure six more readouts and CARA approved $130k to hybridize an additional six 1024x1024 arrays and ten 512x512 arrays, thus increasing the number of devices from which PAIDAI partners may pick. Cold testing of the first four PAIDAI devices at SBRC was carried out in June. This will be followed by array characterization by Al Fowler at NOAO next quarter.