Muonic X-ray energies of the K-series of the light natural elements Be, B, C and N have been determined with a precision of 5 to 10 eV. Equivalent nuclear charge radii have been deduced. The results, expressed in terms of rms radii, are of similar or better accuracy than recent electron scattering data. Of particular interest is the rms radius of carbon as a reference value for elastic electron scattering cross sections. A model-independent evaluation yields 〈r2〉1 2 = 2.467 (17) fm. © 1980.
Schaller, L. A., Schellenberg, L., Ruetschi, A., & Schneuwly, H. (1980). Nuclear charge radii from muonic X-ray transitions in beryllium, boron, carbon and nitrogen. Nuclear Physics, Section A, 343(C), 333–346. https://doi.org/10.1016/0375-9474(80)90656-9