# Results from the Project 8 phase-1 cyclotron radiation emission spectroscopy detector

## TL;DR

The paper reports on the successful development and operation of a prototype cyclotron radiation emission spectroscopy detector aimed at measuring electron energies for neutrino mass determination, demonstrating promising initial results.

## Contribution

First phase prototype of a cyclotron radiation emission spectroscopy detector for neutrino mass measurement, with detailed design, operation, and data analysis procedures.

## Key findings

- Successful operation of the prototype system
- Detection of cyclotron radiation from internal conversion electrons
- Performance metrics achieved in 2014-2015

## Abstract

The Project 8 collaboration seeks to measure the absolute neutrino mass scale by means of precision spectroscopy of the beta decay of tritium. Our technique, cyclotron radiation emission spectroscopy, measures the frequency of the radiation emitted by electrons produced by decays in an ambient magnetic field. Because the cyclotron frequency is inversely proportional to the electron's Lorentz factor, this is also a measurement of the electron's energy. In order to demonstrate the viability of this technique, we have assembled and successfully operated a prototype system, which uses a rectangular waveguide to collect the cyclotron radiation from internal conversion electrons emitted from a gaseous $^{83m}$Kr source. Here we present the main design aspects of the first phase prototype, which was operated during parts of 2014 and 2015. We will also discuss the procedures used to analyze these data, along with the features which have been observed and the performance achieved to date.