# First Calorimetric Measurement of Electron Capture in ${}^{193}$Pt with a Transition Edge Sensor

## TL;DR

This paper reports the first calorimetric measurement of electron capture in ${}^{193}$Pt using a transition edge sensor, providing data to compare with theoretical models and improve understanding of electron capture spectra.

## Contribution

It presents the first experimental calorimetric spectrum of ${}^{193}$Pt electron capture and compares it with theoretical calculations, expanding the study beyond ${}^{163}$Ho.

## Key findings

- Preliminary experimental spectrum obtained for ${}^{193}$Pt
- Comparison with theoretical calculations shows general agreement
- Provides new data for electron capture in ${}^{193}$Pt

## Abstract

The neutrino mass can be extracted from a high statistics, high resolution calorimetric spectrum of electron capture in ${}^{163}$Ho. In order to better understand the shape of the calorimetric electron capture spectrum, a second isotope was measured with a close to ideal absorber-source configuration. ${}^{193}$Pt was created by irradiating a ${}^{192}$Pt-enriched platinum foil in a nuclear reactor. This Pt-in-Pt absorber was designed to have a nearly ideal absorber-source configuration. The measured ${}^{193}$Pt calorimetric electron-capture spectrum provides an independent check on the corresponding theoretical calculations, which have thus far been compared only for ${}^{163}$Ho. The first experimental and theoretically-calculated spectra from this ${}^{193}$Pt-in-Pt absorber are presented and overlaid for preliminary comparison of theory with experiment.