Sn. Shore et Jp. Aufdenberg, ON THE INTERPRETATION OF THE ULTRAVIOLET-SPECTRA OF SYMBIOTIC STARS AND RECURRENT NOVAE .1., The Astrophysical journal, 416(1), 1993, pp. 355-367
We present an analysis of high-resolution spectra of several symbiotic
s and symbiotic novae. We show that the emission lines are severely af
fected by differential extinction caused by absorption lines in the wi
nd of the red giant companion. The major source of the absorbing spect
rum is the forest of lines produced by neutral and singly ionized iron
peak elements. We present models for the effects of this ''iron curta
in,'' and we show that some of the outstanding anomalies in the emissi
on-line fluxes results from the differential absorption by the environ
ment as the path length along the line-of-sight changes; (2) observed
ultraviolet continuum temperatures should, in general, be considerably
lower than that inferred from the Zanstra method or related measures
of the ionization temperature; (3) disappearance of the emission lines
need not imply any changes at all in the intrinsic properties of the
ionizing source but may simply reflect the orbital modulation of its i
ntensity by the circumstellar environment- (4) circumstellar absorptio
n also affects the interpretation of broad emission line profiles; and
(5) the absence of emission lines is not a strong argument against th
e existence of an accretion disk around the hot component.