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arXiv · 2003.11899

Progress in the development of frequency domain multiplexing for the X-ray Integral Field Unit on board the Athena mission

H. Akamatsu·L. Gottardi·J. van der Kuur·C. P. de Vries·M. P. Bruijn·J. A. Chervenak·M. Kiviranta·A. J. van den Linden·B. D. Jackson·A. Miniussi·K. Ravensberg·K. Sakai·S. J. Smith·N. Wakeham
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Abstract

Frequency domain multiplexing (FDM) is the baseline readout system for the X-ray Integral Field Unit (X-IFU) on board the Athena mission. Under the FDM scheme, TESs are coupled to a passive LC filter and biased with alternating current (AC bias) at MHz frequencies. Using high-quality factor LC filters and room temperature electronics developed at SRON and low-noise two-stage SQUID amplifiers provided by VTT, we have recently demonstrated good performance with the FDM readout of Mo/Au TES calorimeters with Au/Bi absorbers. We have achieved a performance requested for the demonstration model (DM) with the single pixel AC bias ($\Delta E=$1.8 eV) and 9 pixel multiplexing ($\Delta E=$2.6 eV) modes. We have also demonstrated 14-pixel multiplexing with an average energy resolution of 3.3 eV, which is limited by non-fundamental issues related to FDM readout in our lab setup.

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H. Akamatsu, L. Gottardi, J. van der Kuur, C. P. de Vries, M. P. Bruijn, J. A. Chervenak, M. Kiviranta, A. J. van den Linden, B. D. Jackson, A. Miniussi, K. Ravensberg, K. Sakai, S. J. Smith, N. Wakeham. 2020-03-26. Progress in the development of frequency domain multiplexing for the X-ray Integral Field Unit on board the Athena mission. https://doi.org/10.1007/s10909-020-02351-3

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