Theoretical Analysis of Level Crossing in a (2)P Atomic State

Two approaches to the analysis of level crossing are presented. A theoretical approach utilizes values of the hyperfine coupling constants to prediet the entire level structure of a system, including all level-crossing data of interest. A second approach suggests a procedure for determining hyperfine parameters with reasonable accuracy, based on three or four measured quantities. Results of this procedure in 2 (2)P lithium give the contact, dipole, and orbital hyperfine coupling constants as -9. 806 +/- 0. 117, -1. 909 +/- 0.034, and 8. 638 +/- 0.039 MHz, respectively. This work reemphasizes the fact that an accurate determination of magnetic his requires three parameters to fully define the three independent magnetic hyperfine Interactions.