Volume 507, Number 3, December I 2009
|Page(s)||1707 - 1710|
|Section||Atomic, molecular, and nuclear data|
|Published online||08 October 2009|
The hyperfine structure of the inversion-rotation transition JK = of NH3 investigated by Lamb-dip spectroscopy
Dipartimento di Chimica “G. Ciamician”, via F. Selmi 2, 40126 Bologna, Italy e-mail: [gabriele.cazzoli;luca.dore;cristina.puzzarini]@unibo.it
Accepted: 10 September 2009
The ground-state inversion-rotation transition of ammonia at 572.498 GHz has been investigated in the laboratory using a source-modulation microwave spectrometer equipped with a double-pass cell. The experiment has been carried out at a pressure lower than 0.5 mTorr, thus enabling to record a Lamb-dip spectrum showing a partial resolution of the magnetic hyperfine structure due to the three proton spins. The achieved high resolution proved to be comparable to that of molecular beam experiments. This measurement provides very precise rest frequencies of the JK = transition and of its hyperfine components, which fall in a spectral region covered by the HIFI instrument on board the Herschel satellite.
Key words: molecular data / methods: laboratory / techniques: spectroscopic / radio lines: ISM
© ESO, 2009
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.