Towards Precision Muonic X-Ray Measurements of Charge Radii of Light Nuclei

Abstract

Precision studies of the properties of nuclei are essential both for understanding nuclear physics at low energy, and for confronting experiment and theory in simple atomic systems. Such comparisons advance our understanding of bound-state quantum electrodynamics and are useful for searching for new physics beyond the Standard Model. The energy levels of muonic atoms are highly susceptible to nuclear structure, especially to the RMS charge radius. The radii of the lightest nuclei ($Z=1,2$) have been determined with high accuracy via laser spectroscopy in muonic atoms, while those of medium mass and above, from X-ray spectroscopy with semiconductor detectors. In this communication we present a new experiment aiming at precision measurements of the radii of light nuclei $3 \leq Z \leq 10$ via single-photon energy measurements with cryogenic microcalorimeters; a quantum sensing technology capable of high efficiency and outstanding resolution for low-energy X-rays