@inproceedings{4d8c00e76d144e679ca80822ebd64241,
title = "Precision measurement of weak transitions from excited states in helium by counting ultracold atoms",
abstract = "The advancing precision of modern atomic spectroscopy is beginning to afford optical tests of fundamental physics in helium through, for instance, nuclear charge radii determinations. Helium therefore provides a testbed as appealing as Hydrogen for spectroscopic tests of QED. Among outstanding discrepancies between predicted and observed Helium transition lines are the 7.5σ difference in the n = 3 singlet-Triplet splitting and the 93σ difference between Martin's measurements of the 23P2 → 53S1 and 23P2 → 53D transitions values, and recent predictions by Drake [3]. We contribute to both of these by measuring five transitions from the 23P2 state, improving on Martin's measurements with an order of magnitude greater precision, and making the first observation of the spin-forbidden 23P2 → 51D2 transition in Helium. Our measurements constrain the 53D and 51D ionization energies of 4He[4] to 150 parts per billion, and the 53S to 28 parts per billion.",
keywords = "Atomic spectroscopy, Bose-Einstein Condensate, Frequency metrology, Metastable Helium, Precision Measurement",
author = "Ross, {J. A.} and Thomas, {K. F.} and Henson, {B. M.} and Hodgman, {S. S.} and A. Truscott and Baldwin, {K. G.H.}",
note = "Publisher Copyright: {\textcopyright} COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.; AOS Australian Conference on Optical Fibre Technology, ACOFT 2019 and Australian Conference on Optics, Lasers, and Spectroscopy, ACOLS 2019 ; Conference date: 09-12-2019 Through 12-12-2019",
year = "2019",
doi = "10.1117/12.2557696",
language = "English",
series = "Proceedings of SPIE - The International Society for Optical Engineering",
publisher = "SPIE",
editor = "Arnan Mitchell and Halina Rubinsztein-Dunlop",
booktitle = "AOS Australian Conference on Optical Fibre Technology, ACOFT 2019 and Australian Conference on Optics, Lasers, and Spectroscopy, ACOLS 2019",
address = "United States",
}