Expérimental
High-precision investigations of atomic systems are invaluable for exploring fundamental physics questions. One innovative avenue involves using quantum sensing x-ray detectors to study exotic atoms, formed when heavier, negatively-charged particles like muons or antiprotons replace electrons in atomic orbitals. The QUARTET program, launching in 2023 at the Paul Scherrer Institute (Switzerland), pioneers the use of magnetic x-ray microcalorimeter detectors to explore the quantum structure of muonic atoms, particularly light muonic atoms like lithium, boron, and beryllium. QUARTET aims to enhance our knowledge of nuclear charge radii and demonstrates the compatibility of these new detectors with exotic particle beams for quantum electrodynamics (QED) tests and searches beyond the standard model. A unique opportunity for students is presented to participate in data analysis, focusing on muonic boron x-ray spectra. Additionally, an ERC-funded project for spectroscopy of antiprotonic atoms at CERN offers a promising future avenue for continuing this topic into a PhD research project in the field of exotic atoms and quantum physics.