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First application of superconducting transition-edge-sensor microcalorimeters to hadronic-atom x-ray spectroscopy



Douglas Bennett, W.Bertrand (Randy) Doriese, Joseph Fowler, Johnathon Gard, James P. Hays-Wehle, Gene C. Hilton, Carl D. Reintsema, Daniel Swetz, Joel Ullom


High-resolution pionic-atom x-ray spectroscopy was performed with an x-ray spectrometer based on a 240-pixel array of superconducting transition-edge-sensor (TES)microcalorimeters at the πM1 beam line of the Paul Scherrer Institute. The pionic-carbon 4 → 3 transition x-ray emission line and its fine structure splitting were observed with a full-width-at-half-maximum energy resolution of 6.8 eV at 6.4 keV. Measured x-ray energies are consistent with calculated electromagnetic values which considered the strong-interaction effect assessed via the Seki-Masutani potential for the 3p energy level, and favor the electronic population of two filled 1s electrons in the K-shell. Absolute energy calibration with an uncertainty of 0.1 eV was demonstrated under a high-rate hadron beam condition of 1.45 MHz. This is the first application of a TES spectrometer to hadronic-atom x-ray spectroscopy and is a key milestone towards next-generation high-resolution kaonic-atom x-ray spectroscopy.
Progress of Theoretical Physics


x-ray spectroscopy, TES microcalorimeters, x-ray fundamental parameters


Bennett, D. , Doriese, W. , Fowler, J. , Gard, J. , Hays-Wehle, J. , Hilton, G. , Reintsema, C. , Swetz, D. and Ullom, J. (2016), First application of superconducting transition-edge-sensor microcalorimeters to hadronic-atom x-ray spectroscopy, Progress of Theoretical Physics, [online], (Accessed April 16, 2024)
Created September 29, 2016, Updated October 12, 2021