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Lyman and Balmer emission following core excitations in methane and ammonia molecules

Jakubowska, Katarzyna ; Vall-llosera, Gemma LU ; Kivimäki, Antti ; Coreno, Marcello ; Melero García, Emilio ; Stankiewicz, Marek and Rachlew, Elisabeth (2007) In Journal of Physics B: Atomic, Molecular and Optical Physics 40(8). p.1489-1500
Abstract
The intensities of hydrogen Lyman-α and Balmer series emission lines as a result of photoexcitation of free CH4 and NH3 molecules at the C 1s and N 1s edges have been measured. For methane, the total fluorescence yield in the visible region (300–650 nm) was also recorded. Excitation functions of the Balmer lines show relative intensity enhancement of Balmer-β emission in comparison with Balmer-α at higher core-to-Rydberg excitations. The Lyman-α emission intensity, in general, follows the relations observed in the corresponding total ion yield measurements. Additionally, the Balmer-γ and -δ yields were measured for ammonia molecules and they show intensity maxima at photon energies shifted closer to the N 1s threshold than Balmer-α and -β.... (More)
The intensities of hydrogen Lyman-α and Balmer series emission lines as a result of photoexcitation of free CH4 and NH3 molecules at the C 1s and N 1s edges have been measured. For methane, the total fluorescence yield in the visible region (300–650 nm) was also recorded. Excitation functions of the Balmer lines show relative intensity enhancement of Balmer-β emission in comparison with Balmer-α at higher core-to-Rydberg excitations. The Lyman-α emission intensity, in general, follows the relations observed in the corresponding total ion yield measurements. Additionally, the Balmer-γ and -δ yields were measured for ammonia molecules and they show intensity maxima at photon energies shifted closer to the N 1s threshold than Balmer-α and -β. A quantum defect analysis is performed to find out which core excitations are responsible for this enhanced intensity. Dissociation pathways leading to the emission in H atoms are discussed. (Less)
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publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Physics B: Atomic, Molecular and Optical Physics
volume
40
issue
8
pages
1489 - 1500
publisher
IOP Publishing
external identifiers
  • scopus:34247098021
ISSN
0953-4075
DOI
10.1088/0953-4075/40/8/003
language
English
LU publication?
no
id
63a4795f-b155-47df-a4c5-7e08360778c2 (old id 1156029)
date added to LUP
2016-04-04 09:24:38
date last changed
2022-01-29 17:43:56
@article{63a4795f-b155-47df-a4c5-7e08360778c2,
  abstract     = {{The intensities of hydrogen Lyman-α and Balmer series emission lines as a result of photoexcitation of free CH4 and NH3 molecules at the C 1s and N 1s edges have been measured. For methane, the total fluorescence yield in the visible region (300–650 nm) was also recorded. Excitation functions of the Balmer lines show relative intensity enhancement of Balmer-β emission in comparison with Balmer-α at higher core-to-Rydberg excitations. The Lyman-α emission intensity, in general, follows the relations observed in the corresponding total ion yield measurements. Additionally, the Balmer-γ and -δ yields were measured for ammonia molecules and they show intensity maxima at photon energies shifted closer to the N 1s threshold than Balmer-α and -β. A quantum defect analysis is performed to find out which core excitations are responsible for this enhanced intensity. Dissociation pathways leading to the emission in H atoms are discussed.}},
  author       = {{Jakubowska, Katarzyna and Vall-llosera, Gemma and Kivimäki, Antti and Coreno, Marcello and Melero García, Emilio and Stankiewicz, Marek and Rachlew, Elisabeth}},
  issn         = {{0953-4075}},
  language     = {{eng}},
  number       = {{8}},
  pages        = {{1489--1500}},
  publisher    = {{IOP Publishing}},
  series       = {{Journal of Physics B: Atomic, Molecular and Optical Physics}},
  title        = {{Lyman and Balmer emission following core excitations in methane and ammonia molecules}},
  url          = {{http://dx.doi.org/10.1088/0953-4075/40/8/003}},
  doi          = {{10.1088/0953-4075/40/8/003}},
  volume       = {{40}},
  year         = {{2007}},
}