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A 14-pixel, multiplexed array of gamma-ray microcalorimeters with 47 eV energy resolution at 103 keV



W.Bertrand (Randy) Doriese, Joel Ullom, James A. Beall, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Kent D. Irwin, John Mates, Carl D. Reintsema, Leila R. Vale, Yizi Xu, Barry L. Zink, Andrew Hoover, Michael W. Rabin, Clifford R. Rudy, Duc Vo


We present a prototype for a high-energy-resolution, high-count-rate, gamma-ray spectrometer intended for nuclear forensics and international nuclear safeguards. The prototype spectrometer is an array of 14 transition-edge-sensor microcalorimeters with an average energy resolution of 47 eV (full width at half maximum) at 103 keV. The best measured energy resolution of a single pixel is 25 eV. A cryogenic, time-division multiplexer reads out the array. We discuss several important topics related to microcalorimeter arrays, including crosstalk between detectors, the uniformity of detector bias conditions, fabrication of the arrays, and scaling the multiplexed readout to more detectors. Our measurements and calculations demonstrate that a kilopixel array of high-resolution microcalorimeters is feasible.
Applied Physics Letters


gamma-ray spectrometer, nuclear forensics, SQUID multiplexer, transition-edge sensor


Doriese, W. , Ullom, J. , Beall, J. , Duncan, W. , Ferreira, S. , Hilton, G. , Horansky, R. , Irwin, K. , Mates, J. , Reintsema, C. , Vale, L. , Xu, Y. , Zink, B. , Hoover, A. , Rabin, M. , Rudy, C. and Vo, D. (2007), A 14-pixel, multiplexed array of gamma-ray microcalorimeters with 47 eV energy resolution at 103 keV, Applied Physics Letters, [online], (Accessed April 21, 2024)
Created May 8, 2007, Updated October 12, 2021