Measurement of the helium 2 P-3(0)-2(3)P(1) fine structure interval
Authors: Minardi F., Bianchini G., Cancio Pastor P., Giusfredi G., Pavone FS., Inguscio M.
Autors Affiliation: European Laboratory for Non-linear Spectroscopy (LENS), Largo E. Fermi 2, Firenze, 50125, Italy; Istituto Nazionale di Ottica (INO), Largo E. Fermi 6, Firenze, I-50125, Italy
Abstract: We report the most accurate measurement of the helium fine structure splitting. The 2(3)P(0)-2(3)P(1) energy splitting is 29 616 949.7 +/- 2.0 kHz. Laser saturation spectroscopy, heterodyne pure frequency determination, and fluorescence detection were combined in a novel experimental approach. The absence of external perturbing magnetic fields, used in earlier experiments, lends confidence to our determined value and allows us to discriminate between contradictory results previously reported. This result, when combined with expected advances in theory, should yield a new value of the fine structure alpha, which may help clarify a presently puzzling experimental situation. [S0031-9007(99)08416-1].
Journal/Review: PHYSICAL REVIEW LETTERS
Volume: 82 Pages from: 1112 to: 1115
KeyWords: Helium; fine-structure; spectroscopyDOI: 10.1103/PhysRevLett.82.1112Citations: 77data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2020-09-13References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here