First application of superconducting transition-edge sensor microcalorimeters to hadronic atom X-ray spectroscopy
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 φM1 beam line of the Paul Scherrer Institute. X-rays emitted by pionic carbon via the 4f → 3d transition and the parallel 4d → 3p transition were observed with a full width at half maximum energy resolution of 6.
