Please use this identifier to cite or link to this item:
|Title:||Atomic fluorescence emitted from a corona discharge in helium above and below saturated vapour pressure|
|Authors:||Shiltagh, Nagham M.|
Mendoza Luna, Luis G.
Watkins, Mark J.
Thornton, Stuart C.
von Haeften, Klaus
|Publisher:||EDP Sciences, Springer Verlag (Germany), Società Italiana di Fisica|
|Citation:||The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics, 2018, 72 (5)|
|Abstract:||A new apparatus was constructed to investigate the visible and near infrared fluorescence spectroscopy of electronically excited helium over a wide range of pressures and temperatures, covering both the gaseous and liquid phases. To achieve sufficient throughput, increased sensitivity was established by employing a micro-discharge cell and a high performance lens system that allows for a large collection solid angle. With this set-up, several thousand spectra were recorded. The atomic 3s 1S → 2p 1P and 3s 3S → 2p 3P atomic transitions showed line shifts, spectral broadening and intensity changes that were dependent in magnitude on pressure, temperature and thermodynamic phase. While in the gas phase the lines showed little dependency on the discharge cell temperature, the opposite was observed for the liquid phase, suggesting that a significant number of atoms were solvated. Triplet lines were up to a factor of 50 times stronger in intensity than the singlet lines, depending on pressure. When taking the particle density into account, this effect was stronger in the gas phase than in the liquid phase of helium. This was attributed to the recombination of He2 +, He3 + and He4 + with electrons, which is facilitated in the gas phase because of the significantly higher mobility.|
|Rights:||Copyright © the authors, 2018. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.|
|Description:||Contribution to the Topical Issue “Dynamics of Molecular Systems (MOLEC 2016)”, edited by Alberto Garcia-Vela, Luis Banares and Maria Luisa Senent.|
|Appears in Collections:||Published Articles, Dept. of Physics and Astronomy|
Files in This Item:
|10.1140%2Fepjd%2Fe2017-80322-4.pdf||Published (publisher PDF)||1.46 MB||Adobe PDF||View/Open|
Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.