ELECTRON - Development of High Resolution Metallic Microcalorimeters for a Future Neutrino Mass Experiment

Metallic Magnetic Calorimeters (MMCs) are low temperature single particle detectors, whose working principle is based on quantum technology. Due to their excellent energy resolution, near linear detector response, fast signal rise time and close to 100% quantum efficiency, MMCs outperform conventional detectors by several orders of magnitude, making them interesting for a wide range of different applications. The aim of the ELECTRON project is to demonstrate, for the first time, that MMC based detectors can be employed for a high resolution spectroscopy of external electron sources, namely electron-gun, krypton-83m and tritium. Technology and methods developed within the context of the ELECTRON project will pave a way for the next generation neutrino experiments with tritium, employing a differential detector based on quantum technology. We present the first measurements of the 83mKr spectrum performed with an MMC-based detector, as well as the efforts put towards the first ever measurements of the tritium β-decay spectrum using a novel compact tritium source.