Precision determination of the fine-structure splittings of the 5d and 6d states in potassium
The fine-structure splittings of the inverted 5 and 62D states of potassium were measured by observing level-crossing signals at high magnetic fields. TheD levels were populated using step-wise excitations, employing two CW tunable dye lasers. For the fine-structure intervals dW we find: dW (5d)= -15,102.0 (5) MHz anddW(6d) = -7,965.8 (6) MHz. These values are about 100 times more accurate than pr
