Physical Review A - Atomic, Molecular, and Optical Physics
An rms nuclear charge radius rc =1.9642 (11) fm for He3 is derived from measurements of the 2 S13 -2 P03 isotope shift combined with the best available data on the fine structure of He4, the hyperfine structure of He3, and an assumed rc =1.673 (1) fm for He4. The result removes a small discrepancy between some older spectroscopic determinations of rc for He3 from this transition and a more recent measurement. © 2006 The American Physical Society.
Morton, D. C.; Wu, Q.; and Drake, Gordon W. F.. (2006). Nuclear charge radius for He3. Physical Review A - Atomic, Molecular, and Optical Physics, 73 (3), 34502-1-34502-3.