Applications to Nuclear Size Measurements

As stated in Section 1, one of fhe goals of this work is to use the comparison between theory and experiment for the isotope shift to determine the nuclear charge radius for various isotopes of helium and other atoms. One of the most interesting and important examples is the charge radius of the Tialo nucleus He. For a light atom such as helium, the energy shift due to the finite nuclear size is given to an excellent approximation by 

TABLE 4.8 Table of nuclear masses used in the calculations. Units are atomic mass units  

Reaction collision Elastic collision Atomic isotope shift 

Since the goal of the experiment is to determine the nuclear charge radius for He, the final step is to adjust fc so as to eliminate the small discrepancy of 0.046(56) MHz shown in Table 4.7. The various contributions to the isotope shift in Table 4.7 can be collected together and expressed in the form 

TABLE 4.9 Contributions to the Li- Li isotope shift for the Is 3s S-ls 2s transition. Units are MHz 

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