FASPAX: A fast, integrating detector for the APS-upgrade

FASPAX (Fermi-Argonne Semiconductor Pixel Array X-ray detector) has been planned as a fast integrating area detector with wide dynamic range for time resolved applications at the upgraded Advanced Photon Source (APS). The detector will achieve a burst image rate of 13 MHz, matching the bunch rate of the proposed storage ring timing mode. A unique three gain charge splitting integration circuit will permit wide dynamic range — from single photon sensitivity to 10 5 photons/pixel (100 μm × 100 μm) in a single exposure. Incorporation of a novel interposer layer in the hybrid stack will permit large area sensors without the usual coverage gaps associated with hybrid pixel devices. The detector will provide access to the full tem-poral resolution of the APS, and enable novel science, such as pump-probe studies of irreversible systems. The APS Upgrade is currently funding development of small prototypes (1.2 cm × 1.2 cm) that will be tested in the next few years. This work will present an overview of the detector, and current status of the detector development.