Extended Data Fig. 1: Detailed level scheme of the two-step excitation.
From: Laser spectroscopic characterization of the nuclear-clock isomer 229mTh
Transitions and electronic configurations of the initial (g), intermediate (i) and excited (e) states relevant to the experiment are shown, labelled by their energy in cm−1 and the electronic angular momentum J. Hyperfine sub-levels are indicated by their total angular momentum F and Fm. Transitions belonging to the same intermediate hyperfine level are depicted with the same colour. The hyperfine intervals are calculated from the hyperfine constants A and B presented in Table 1.
