Measurement of the mercury (6s6p) 3P1-state lifetime in the frequency domain from integrated absorbance data
Year: 2022
Authors: Gravina S., Clivati C., Castrillo A., Fasci E., Chishti N.A., Galzerano G., Levi F., Gianfrani L.
Autors Affiliation: Univ Campania Luigi Vanvitelli, Dipartimento Matemat & Fis, I-81100 Caserta, Italy; Ist Nazl Ric Metrol INRiM, I-10135 Turin, Italy; CNR, Ist Foton & Nanotecnol, I-20133 Milan, Italy.
Abstract: Quantitative UV laser absorption spectroscopy is implemented to measure the strength of the (6s2) 1S0 -> (6s6p)3P1 intercombination transition of Hg atoms near the wavelength of 253.7 nm and to retrieve the lifetime of the excited state. Tunable, single-mode, coherent radiation in the deep UV is produced through a double -stage second-harmonic generation process, starting from the output radiation of an external-cavity diode laser at 1014.8 nm. This latter is referenced to an optical frequency comb synthesizer. The measurement strategy exploits the relationship between the strength of an optical transition and the spontaneous emission Einstein coefficient. The complete uncertainty budget leads to an overall relative uncertainty of 0.6%, with a statistical contribution of 0.28 ns, which is the lowest ever obtained for the (6s6p) 3P1 lifetime. The new value, amounting to 125.12 +/- 0.79 ns, compares well with most of the past determinations within two times the quoted uncertainties. Despite this, it does not agree with the weighted average of the 12 prior values, thus suggesting that a critical reassessment of the uncertainty of some of the past measurements is probably necessary.
Journal/Review: PHYSICAL REVIEW RESEARCH
Volume: 4 (3) Pages from: 33240-1 to: 33240-7
More Information: This research was funded by the Italian Ministry for University and Research (Program Type PRIN 2015) and by Universita degli studi della Campania Luigi Vanvitelli within the V:ALERE program (Call published in 2019, Project V:ANS). The authors are grateful to Giuseppina Lopardo and Fabio Bertiglia for providing temperature traceability of the isothermal cell.KeyWords: Spectroscopy; AbundanceDOI: 10.1103/PhysRevResearch.4.033240Citations: 4data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2025-03-30References taken from IsiWeb of Knowledge: (subscribers only)
