Hard X-ray Fluorescence measurements with TESs at the Advanced Photon Source

TL;DR

This paper reports on the development and testing of TES-based spectrometers for hard X-ray fluorescence measurements at the APS, showing improved resolution and capabilities for complex samples.

Contribution

It introduces a TES-based instrument for the APS, with prototype arrays demonstrating high energy resolution and successful measurements of multi-element samples.

Findings

Achieved 11.2 eV energy resolution with TES arrays.

Demonstrated TES advantages over silicon drift detectors.

Successfully measured complex multi-element fluorescence spectra.

Abstract

Transition Edge Sensor (TES) spectrometers for hard X-ray beamline science will enable improved X-ray emission and absorption spectroscopy in the information-rich 2 to 20 keV energy range. We are building a TES-based instrument for the Advanced Photon Source (APS) synchrotron, to be made available to beamline users. 24-pixel prototype arrays have recently been fabricated and tested. The first spectroscopy measurements using these arrays are promising, with a best single-pixel energy resolution of 11.2 eV and saturation energy > 20 keV. We present a series of recent X-ray Fluorescence measurements involving transition metal elements and multi-element samples with closely spaced emission lines, in particular a Cu-Ni-Co thin film and a foil of Cu and Hf. The TES-measured spectra are directly compared to spectra measured with silicon drift detectors at an APS beamline, demonstrating the improved X-ray science made possible by TES spectrometers.