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Astron. Astrophys. 329, 792-798 (1998)

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Density effects on the electronic contribution to hydrogen Lyman [FORMULA] Stark profiles

O. Motapon 1, 2

1 DAMAP and URA 812 du CNRS, Observatoire de Paris, F-92195 Meudon Cedex, France
2 Département de Physique, Faculté des Sciences, B.P. 24157, Université de Douala, Cameroon

Received 23 September 1996 / Accepted 17 June 1997


The quantum unified theory of Stark broadening (Tran Minh et al. 1975, Feautrier et al. 1976) is used to study the density effects on the electronic contribution to the hydrogen Lyman [FORMULA] lineshape. The contribution of the first angular momenta to the total profile is obtained by an extrapolation method, and the results agree with other approaches. The comparison made with Vidal et al. (1973) shows a good agreement; and the electronic profile is found to be linear in density for [FORMULA] greater than 8Å for densities below [FORMULA] cm-3, while the density dependence becomes more complex for [FORMULA] less than 8Å. The wing profiles are calculated at various temperatures scaling from 2500 to 40000K and a polynomial fit of these profiles is given.

Key words: lines: profiles – atomic processes

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© European Southern Observatory (ESO) 1998

Online publication: December 8, 1997