Developments on frequency domain multiplexing readout for large arrays of transition-edge sensor X-ray micro-calorimeters

D. Vaccaro; H. Akamatsu; L. Gottardi; M. de Wit; M. P. Bruijn; J. van der Kuur; K. Nagayoshi; E. Taralli; K. Ravensberg; J. R. Gao; J. W. A. den Herder

doi:10.1007/s10909-024-03099-w

arXiv · 2403.02989

Developments on frequency domain multiplexing readout for large arrays of transition-edge sensor X-ray micro-calorimeters

D. Vaccaro·H. Akamatsu·L. Gottardi·M. de Wit·M. P. Bruijn·J. van der Kuur·K. Nagayoshi·E. Taralli·K. Ravensberg·J. R. Gao·J. W. A. den Herder

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Abstract

At SRON we have been developing X-ray TES micro-calorimeters as backup technology for the X-ray Integral Field Unit (X-IFU) of the Athena mission, demonstrating excellent resolving powers both under DC and AC bias. We also developed a frequency-domain multiplexing (FDM) readout technology, where each TES is coupled to a superconducting band-pass LC resonator and AC biased at MHz frequencies through a common readout line. The TES signals are summed at the input of a superconducting quantum interference device (SQUID), which performs a first amplification at cryogenic stage. Custom analog front-end electronics and digital boards take care of further amplifying the signals at room temperature and of the modulation/demodulation of the TES signals and bias carrier, respectively. We report on the most recent developments on our FDM technology, which involves a two-channel demonstration with a total of 70 pixels with a summed energy resolution of 2.34 +/- 0.02 eV at 5.9 keV without spectral performance degradation with respect to single-channel operation. Moreover, we discuss prospects towards the scaling-up to a larger multiplexing factor up to 78 pixels per channel in a 1-6 MHz readout bandwidth.

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D. Vaccaro, H. Akamatsu, L. Gottardi, M. de Wit, M. P. Bruijn, J. van der Kuur, K. Nagayoshi, E. Taralli, K. Ravensberg, J. R. Gao, J. W. A. den Herder. 2024-03-05. Developments on frequency domain multiplexing readout for large arrays of transition-edge sensor X-ray micro-calorimeters. https://doi.org/10.1007/s10909-024-03099-w

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