The photodetector array camera and spectrometer (PACS) for the Herschel Space Observatory

摘要

The Photodetector Array Camera and Spectrometer (PACS) is one of the three science instruments for ESA's far infrared and submillimetre observatory, Herschel. It employs two Ge:Ga photoconductor arrays (stressed and unstressed) with 16 x 25 pixels, each, and two filled Si bolometer arrays with 16 x 32 and 32 x 64 pixels, respectively, to perform imaging line spectroscopy and imaging photometry in the 57-210 micron wavelength band. In photometry mode, it will simultaneously image two bands, 60-85 micron or 85-130 micron and 130-210 micron, over a field of view of ~ 1.75'x3.5', with full beam sampling in each band. In spectroscopy mode, it will image a field of ~ 50"x50", resolved into 5 x 5 pixels, with an instantaneous spectral coverage of ~ 1500 km/s and a spectral resolution of ~ 75 - 300 km/s. In both modes background-noise limited peformance is expected, with sensitivities (5σ in 1h) of ~3 mJy or 3-10x10-18 W/m2, respectively.