The Photodetector Array Camera and Spectrometer (PACS) on?the?Herschel Space Observatory

摘要

The Photodetector Array Camera and Spectrometer (PACS) is one of the three scienceinstruments on ESA's far infrared and submillimetre observatory. It employs two Ge:Ga photoconductor arrays (stressed andunstressed) with pixels, each, and two filled siliconbolometer arrays with and pixels,respectively, to perform integral-field spectroscopy and imagingphotometry in the 60-210m wavelength regime. In photometry mode, itsimultaneously images two bands, 60-85m or 85-125m and125-210m, over a field of view of ,withclose to Nyquist beam sampling in each band. In spectroscopy mode, itimages a field of ,resolved into pixels, with an instantaneous spectral coverage of kms-1 anda spectral resolution of 175kms-1. We summarise the design of theinstrument, describe observing modes, calibration, and data analysismethods, and present our current assessment of the in-orbit performanceof the instrument based on the performance verification tests. PACS isfully operational, and the achieved performance is close to or betterthan the pre-launch predictions.Key words: space vehicles: instruments - instrumentation: photometers - instrumentation: spectrographs