In the JCMT Science Archive one can find data obtained with the following continuum receivers.
|UKT14||1989-02-09 to 1997-10-29|
|SCUBA||1997-05-22 to 2005-06-06|
UKT14 was a single pixel bolometer. It had filters at 2000, 1300, 1100, 850, 800, 750, 450, and 350 micron. The beamwidth ranged from 27 arcsec at 2000 micron to 6 arcsec at 350 micron. See A millimetre/submillimetre common user photometer for the James Clerk Maxwell Telescope. Duncan et al. for more information about UKT14.
SCUBA was a submillimetre continuum array receiver, with a field of view 2.3 arcmin in diameter. It had two hexagonal arrays of bolometric detectors (or pixels); the Long-Wave (LW) array had 37 pixels, while the Short-Wave (SW) array had 91 pixels. Both arrays were used simultaneously by means of a dichroic beamsplitter, which in SCUBA’s prime mode corresponded to observing at 450 microns on the SW array and 850 microns on the LW array. Each of the pixels had diffraction-limited resolution, corresponding to about 7.5 arcseconds at 450 micron, and 14 arcseconds at 850 micron. The arrays could be used to make maps, in either the “jiggle-map” or “scan-map” modes, or as photometers, where only the central pixel on each array is used. A polarimeter could also be attached to the front window of SCUBA which then allows polarimetric photometry and jiggle-map modes.
SCUBA’s original design allowed for observations also at 350, 750, 1100, 1300 and 2000 microns, but due to engineering problems which began in 1997, these windows were not available.
SCUBA was cooled to below 100mK by means of a dilution refrigerator, which means SCUBA’s sensitivity is limited by the photon noise from the sky and telescope background at all wavelengths. The background power was further limited by a combination of single-moded conical feedhorns and narrow-band filters.
See SCUBA: a common-user submillimetre camera operating on the James Clerk Maxwell Telescope. Holland et al. for more information about SCUBA.