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Modeling the wind structure of AG Peg by fitting of C IV and N V resonance doublets

Eriksson, Mattias LU ; Johansson, Sveneric LU and Wahlgren, Glenn LU (2004) In Astronomy & Astrophysics 422(3). p.987-999
Abstract
The latest outburst of AG Peg has lasted for 150 years, which makes itthe slowest nova eruption ever recorded. During the time of IUEobservations (1978-1995) line profiles and intensity ratios of the N Vand C IV doublet components changed remarkably, and we discuss plausiblereasons. One of them is radiative pumping of Fe II which is investigatedby studying the fluorescence lines from pumped levels. Three Fe IIchannels are pumped by C IV and one by N V. The pumping rates of thoseFe II channels as derived by the modeling agree well with the strengthsof the Fe II fluorescence lines seen in the spectra. We model the C IVand N V resonance doublets in IUE spectra recorded between 1978 and 1995in order to derive optical depths, expansion... (More)
The latest outburst of AG Peg has lasted for 150 years, which makes itthe slowest nova eruption ever recorded. During the time of IUEobservations (1978-1995) line profiles and intensity ratios of the N Vand C IV doublet components changed remarkably, and we discuss plausiblereasons. One of them is radiative pumping of Fe II which is investigatedby studying the fluorescence lines from pumped levels. Three Fe IIchannels are pumped by C IV and one by N V. The pumping rates of thoseFe II channels as derived by the modeling agree well with the strengthsof the Fe II fluorescence lines seen in the spectra. We model the C IVand N V resonance doublets in IUE spectra recorded between 1978 and 1995in order to derive optical depths, expansion velocities, and theemissivities of the red giant wind, the white dwarf wind and theircollision region. The derived expansion velocities are ∼60 kms<SUP>-1</SUP> for the red giant wind and ∼700 km s<SUP>-1</SUP> forthe white dwarf wind. We also suggest a fast outflow from the system at∼150 km s<SUP>-1</SUP>. The expansion velocity is slightly higherfor N V than for C IV. Emission from the collision region stronglyaffects the profile of the N V and C IV resonance doublets indicatingits existence. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
atomic processes, line: formation, line: profiles, stars: binaries: symbiotic, stars: individual: AG Peg
in
Astronomy & Astrophysics
volume
422
issue
3
pages
987 - 999
publisher
EDP Sciences
external identifiers
  • wos:000223659500022
  • scopus:3442884022
ISSN
0004-6361
DOI
10.1051/0004-6361:20034086
language
English
LU publication?
yes
id
d4bc620f-21df-4e86-b631-9dcd776c3d5f (old id 134109)
date added to LUP
2007-07-13 07:39:11
date last changed
2017-08-13 04:25:38
@article{d4bc620f-21df-4e86-b631-9dcd776c3d5f,
  abstract     = {The latest outburst of AG Peg has lasted for 150 years, which makes itthe slowest nova eruption ever recorded. During the time of IUEobservations (1978-1995) line profiles and intensity ratios of the N Vand C IV doublet components changed remarkably, and we discuss plausiblereasons. One of them is radiative pumping of Fe II which is investigatedby studying the fluorescence lines from pumped levels. Three Fe IIchannels are pumped by C IV and one by N V. The pumping rates of thoseFe II channels as derived by the modeling agree well with the strengthsof the Fe II fluorescence lines seen in the spectra. We model the C IVand N V resonance doublets in IUE spectra recorded between 1978 and 1995in order to derive optical depths, expansion velocities, and theemissivities of the red giant wind, the white dwarf wind and theircollision region. The derived expansion velocities are ∼60 kms&lt;SUP&gt;-1&lt;/SUP&gt; for the red giant wind and ∼700 km s&lt;SUP&gt;-1&lt;/SUP&gt; forthe white dwarf wind. We also suggest a fast outflow from the system at∼150 km s&lt;SUP&gt;-1&lt;/SUP&gt;. The expansion velocity is slightly higherfor N V than for C IV. Emission from the collision region stronglyaffects the profile of the N V and C IV resonance doublets indicatingits existence.},
  author       = {Eriksson, Mattias and Johansson, Sveneric and Wahlgren, Glenn},
  issn         = {0004-6361},
  keyword      = {atomic processes,line: formation,line: profiles,stars: binaries: symbiotic,stars: individual: AG Peg},
  language     = {eng},
  number       = {3},
  pages        = {987--999},
  publisher    = {EDP Sciences},
  series       = {Astronomy & Astrophysics},
  title        = {Modeling the wind structure of AG Peg by fitting of C IV and N V resonance doublets},
  url          = {http://dx.doi.org/10.1051/0004-6361:20034086},
  volume       = {422},
  year         = {2004},
}