Absorption spectra of Fe L-lines in Seyfert 1 galaxies

J. Dubau; D. Porquet; O. Z. Zabaydullin

doi:10.1016/s0022-4073(03)00065-7

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Absorption spectra of Fe L-lines in Seyfert 1 galaxies

J. Dubau·D. Porquet·O. Z. Zabaydullin

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Abstract

Absorption L-lines of iron ions are observed, in absorption, in spectra of Seyfert 1 galaxies by the new generation of X-ray satellites: Chandra (NASA) and XMM-Newton (ESA). Lines associated to Fe23+ to Fe17+ are well resolved. Whereas, those corresponding to Fe16+ to Fe6+ are unresolved. Forbidden transitions of the Fe16+ to Fe6+ ions were previously observed, for the same objects, in the visible and infra-red regions, showing that the plasma had a low density. To interpret X-ray, visible and infra-red data, astrophysical models assume an extended absorbing medium of very low density surrounding an intense X-ray source. We have calculated atomic data (wavelengths, radiative and autoionization rates) for n=2 to n'=3-4 transitions and used them to construct refined synthetic spectra of the unresolved part of the L-line spectra.

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J. Dubau, D. Porquet, O. Z. Zabaydullin. 2003-03-19. Absorption spectra of Fe L-lines in Seyfert 1 galaxies. https://doi.org/10.1016/s0022-4073(03)00065-7

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