The nuclear charge radius of 13C

Scientists have precisely measured the root-mean-square charge radius of the carbon-13 nucleus using advanced laser spectroscopy on highly charged ions. This new measurement significantly improves the accuracy of this fundamental nuclear property, reducing uncertainty by a factor of six compared to previous electron-based determinations. The research also highlights a notable disagreement, a three-sigma discrepancy, between this new result and data obtained from muonic atom spectroscopy.

This precise measurement and the observed discrepancy with other methods are crucial for understanding nuclear structure and potentially resolving long-standing puzzles in nuclear physics.