Open AccessSpectral indications of ejection of mass by the symbiotic binary Z Andromedae during its 2000–2002 outburst ★
Author(s) -
Tomov N. A.,
Tomova M. T.,
Bisikalo D. V.
Publication year - 2008
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2008.13597.x
Subject(s) - physics , astrophysics , emission spectrum , accretion (finance) , orbital plane , spectral line , astronomy , line (geometry) , orbital period , orbital inclination , stellar mass , light curve , binary number , stars , star formation , geometry , mathematics , arithmetic
High‐resolution observations in the region of the lines Hα, He ii λ 4686 and Hγ of the spectrum of the symbiotic binary Z Andromedae were performed in the quiescent state of the system and also during its outburst phase in 2000–2002. The triplet lines of He i had P Cygni profiles indicating stellar wind with a velocity of 60 km s −1 from the hot secondary. This wind created an absorption dip in the emission profile of the line Hγ. The lines Hγ and He ii λ 4686 had a broad emission component, indicating an optically thin stellar wind with a velocity of about 500 km s −1 . The intensity of the broad component reached its maximum together with the optical light. To explain the observations, a model with an accretion disc was proposed, where the velocity of the wind from the accretor is supposed to be 500 km s −1 . The accretion disc is responsible for the breaking of the stellar wind close to the orbital plane where its velocity decreases to about 60 km s −1 . The mass‐loss rate of the accretor at the time of a maximal light was obtained of 2.4 × 10 −7 (d/1.12 kpc) 3/2 M ⊙ yr −1 and decreased to 1.0 × 10 −7 (d/1.12 kpc) 3/2 M ⊙ yr −1 in 2001 October.