This paper summarizes a preliminary design concept for the focal plane assembly of the X-ray Integral Field Unit on theAthena spacecraft, an imaging microcalorimeter that will enable high spectral resolution imaging and point-sourcespectroscopy. The instrument's sensor array will be a ~ 3840-pixel transition edge sensor (TES) microcalorimeter array,with a frequency domain multiplexed SQUID readout system allowing this large-format sensor array to be operatedwithin the thermal constraints of the instrument's cryogenic system. A second TES detector will be operated in closeproximity to the sensor array to detect cosmic rays and secondary particles passing through the sensor array for off-linecoincidence detection to identify and reject events caused by the in-orbit high-energy particle background. The detectors,operating at 55 mK, or less, will be thermally isolated from the instrument cryostat's 2 K stage, while shielding andfiltering within the FPA will allow the instrument's sensitive sensor array to be operated in the expected environmentduring both on-ground testing and in-flight operation, including straylight from the cryostat environment, low-energyphotons entering through the X-ray aperture, low-frequency magnetic fields, and high-frequency electric fields.
|Numero di pagine||8|
|Stato di pubblicazione||Published - 2016|