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Signal Readout for Transition-Edge Sensor X-ray Imaging Spectrometers



Hiroki Akamatsu, W.Bertrand (Randy) Doriese, John Mates, Brian Jackson


Arrays of low-temperature microcalorimeters provide a promising technology for X-ray astrophysics: the imaging spectrometer. A camera with at least several thousand pixels, each of which has an energy-resolving power (E∕ΔE_FWHM) of a few thousand across a broad energy range (200 eV to 10 keV or higher), would be a revolutionary instrument for the study of energetic astrophysical objects and phenomena. Signal readout is a critical enabling technology. Multiplexed readout, in which signals from multiple pixels are combined into a single amplifier channel, allows a kilopixel-scale microcalorimeter array to meet the stringent requirements for power consumption, mass, volume, and cooling capacity in orbit. This chapter describes three different multiplexed-readout technologies for transition-edge sensor microcalorimeters: time-division multiplexing, frequency-domain multiplexing, and microwave-SQUID multiplexing. For each multiplexing technique, we present the basic method, discuss some design considerations and parameters, and show the state of the art. The chapter concludes with a brief discussion of future prospects.
Handbook of X-ray and Gamma-ray Astrophysics
Publisher Info
Springer Nature, Berlin,


X-ray spectrometer, Microcalorimeter, Cryogenic electronics, signal readout, multiplexed readout, Semiconductor calorimeter, Transition-Edge Sensor, Metallic-Magnetic calorimeter, SQUID


Akamatsu, H. , Doriese, W. , Mates, J. and Jackson, B. (2023), Signal Readout for Transition-Edge Sensor X-ray Imaging Spectrometers, Handbook of X-ray and Gamma-ray Astrophysics, Springer Nature, Berlin, , [online],, (Accessed May 20, 2024)


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Created May 20, 2023, Updated June 8, 2023