Speaker
Description
JUNGFRAU is the charge integrating hybrid photon detector designed for SwissFEL, the free electron laser at the Paul Scherrer Institut. Three independently and automatically switching gains per pixel ensure both a low readout noise of 55 electrons and a large dynamic range of $10^4$ 12.4 keV photons [1]. During the last year, two 16 megapixel JUNGFRAU detectors were constructed at PSI and installed as the principal detector systems at SwissFEL. Several smaller JUNGFRAU detector systems act as additional detectors and monitors. These systems have already been integrated and used successfully in the pilot and first SwissFEL experiments [2].
For successful operation, the JUNGFRAU requires an in-depth characterisation and energy calibration. This has required a campaign of dedicated laboratory and testbeam based measurements, to fully probe the behaviour of the 1.0 ASIC. Lessons from these measurements are crucial to ensure the optimal operation of the existing systems [3]. Moreover, a good understanding of the shortcomings of the current ASIC has allowed the redesign of an improved, pin compatible JUNGFRAU 1.1 ASIC, where the non critical shortcomings are addressed. In addition, the new readout chip is expected to improve the noise and linearity performance.
In this contribution the JUNGFRAU photon detector will be introduced and described. First operational and experimental experiences from SwissFEL will be shared. Test beam and laboratory measurements crucial to understanding the system will be presented. Depending on the delivery date of the new ASIC, preliminary results from its electrical characterisation will be shown.
[1] Mozzanica et al., Characterization results of the JUNGFRAU full scale readout ASIC (2016)
[2] Mozzanica et al., The JUNGFRAU Detector for Applications at Synchrotron Light Sources and XFELs (2018)
[3] Redford et al., Operation and performance of the JUNGFRAU photon detector during first FEL and synchrotron experiments (2018)
