We describe a series of microcalorimeter X-ray spectrometers designed for a broad suite of
measurement applications. The chief advantage of this type of spectrometer is that it can be …

Future X-ray astrophysics experiments require multiplexed readout of high fill-factor, kilo-
pixel arrays of transition-edge sensors (TESs), with very high spectral resolution over a …

The kaonic helium-4 3d→ 2p X-ray transition was measured in a gaseous target, where
Compton scattering in helium is negligible. The X-rays were detected with large-area Silicon …

Time-division multiplexing (TDM) is the backup readout technology for the X-ray Integral
Field Unit (X-IFU), a 3168-pixel X-ray transition-edge sensor (TES) array that will provide …

The first observation of the kaonic 3He 3d→ 2p transition was made, using slow K− mesons
stopped in a gaseous 3He target. The kaonic atom X-rays were detected with large-area …

We report a new test of quantum electrodynamics (QED) for the w (1 s 2 p P 1 1→ 1 s 2 S 0
1) x-ray resonance line transition energy in heliumlike titanium. This measurement is one of …

We introduce a new technique for determining x-ray fluorescence line energies and widths,
and we present measurements made with this technique of 22 x-ray L lines from lanthanide …

Time-division multiplexing (TDM) of transition-edge-sensor (TES) microcalorimeters is being
developed as the readout technology for the Athena X-ray integral field unit (X-IFU) and …

The x-ray atomic properties of nickel (Ni) were investigated in a unique approach combining
different experimental techniques to obtain new, useful and reliable values of atomic …

We use an array of transition-edge sensors, cryogenic microcalorimeters with 4 eV energy
resolution, to measure L x-ray emission-line profiles of four elements of the lanthanide …