Nuclear Charge Radius of ${}^9$Be from Muonic Atom Spectroscopy Using a Microcalorimeter

Ofir Eizenberg, Shikha Rathi, Andreas Abeln +34

The $2p\to 1s$ transition energy in muonic ${}^9$Be was measured using a metallic magnetic calorimeter, resulting in $E_{2p\to 1s}=33391.48(34)$eV. The result is 30 times more pre…