2012

den Hartog, Roland; Audley, M.D.; Beyer, J.; Boersma, D.; Bruijn, M.; Gottardi, L.; Hoevers, H.; Hou, R.; Keizer, G.; Khosropanah, P.; Kiviranta, Mikko; de Korte, P.; van Der Kuur, J.; van Leeuwen, B.-J.; Nieuwenhuizen, A.C.T.; van Winden, P.

SRON is developing an electronic read-out system for an array of transition edge sensors (TES) based on the techniques of frequency domain multiplexing (FDM) and base-band feedback (BBFB). The astronomical applications of our system are the read-out of soft X-ray micro-calorimeters in a potential instrument on the European X-ray mission-under-study Athena and far-IR bolometers for the SAFARI instrument on the Japanese mission SPICA. In this paper we demonstrate the simultaneous locking of up to 51 BBFB loops. While locked, the in-band read-out noise of the loops is shown to reach the 10~pA/√Hz level required for these missions.