Development of a compact cryogenic Penning trap with permanent magnets: An intermediate step toward the Shanghai Penning Trap

Penning traps, renowned for their unparalleled precision in determining fundamental properties, such as mass and magnetic moments, are cornerstone instruments in modern physics. Their applications span from nuclear structure studies to stringent tests of quantum electrodynamics and CPT invariance. Although Penning traps have been demonstrated for fundamental studies, often employing superconducting magnets, their high cost and operational complexity remain challenges. In this work, we report the