The nova type outburst of the symbiotic star AS 296

1990 ◽  
Vol 122 ◽  
pp. 440-441
Author(s):  
Ulisse Munari
Keyword(s):  
Orbital Period ◽  
Active Phase ◽  
Borderline Case ◽  
Symbiotic Star ◽  
Symbiotic Stars ◽  
Late Type ◽  
Type Giant ◽  
One Year

AbstractThe photometric and spectroscopic evolutions, displayed by AS 296 since the June 1988 outburst ([1]), are presented and discussed. The main features of the model outlined by [2], [3] and [4], are confirmed and further developped. An orbital period of about 3 years is inferred from Hα modulation (see [5]).The outburst originated from a TNR event in the accreted envelope of a WD. The IUE and optical spectroscopic evolution agrees with the expected scenario for degenerate conditions in the accreted material, while the high quiescence luminosity of the WD would indicate nondegenerate conditions.The late type giant passed unchanged the outburst. Also the region of Hα formation was not touched by the eruption.After one year the system has not yet reached the quiescence again. The photometric evolution displayed by AS 296 up to June 15, 1989 is presented in Fig.1.In Tab.1, the main features exhibited by symbiotic stars that have experienced a TNR event are summarized. The first 8 objects in the table are usually collectively called "symbiotic novae". They distinguish themselves for the very long outburst duration. At present, AS 296 appears to be a borderline case of such class, and a firm understanding needs to wait for the end of current active phase.

Observations of Bipolar Mass Flow from Symbiotic Stars

1988 ◽  
Vol 103 ◽  
pp. 85-88
Author(s):  
J. Solf
Keyword(s):  
Accretion Disk ◽  
Mass Flow ◽  
Spectral Resolution ◽  
High Velocity ◽  
Binary Star ◽  
High Spectral Resolution ◽  
Symbiotic Stars ◽  
Late Type ◽  
Spectroscopic Observations ◽  
Type Giant

AbstractSpectroscopic observations of high spatial and high spectral resolution indicate that mass flow from symbiotic stars generally exhibits a bipolar pattern. Besides the polar features moving at velocities up to several 100 km/s, equatorial structures of much lower expansion rate are present in some cases. Mostly, the high-velocity components appear to be highly collimated and hence can be considered as “jets”. The jets probably originate from an accretion disk within a binary star where mass from a late-type giant is accreted by a compact companion.

scholarly journals UV spectroscopy confirms SU Lyn to be a symbiotic star

2020 ◽  
Vol 500 (1) ◽  
pp. L12-L16
Author(s):  
Vipin Kumar ◽  
Mudit K Srivastava ◽  
Dipankar P K Banerjee ◽  
Vishal Joshi
Keyword(s):  
Near Infrared ◽  
Uv Spectroscopy ◽  
Symbiotic Star ◽  
Symbiotic Stars ◽  
High Excitation ◽  
Uv Spectrum ◽  
Infrared Observations ◽  
X Ray ◽  
The Galaxy ◽  
Type Giant

ABSTRACT SU Lyn, a star that ostensibly appears to be an unremarkable late M type giant, has recently been proposed to be a symbiotic star largely based on its hard X-ray properties. The star does not display, in low-resolution optical spectra, the high excitation lines typically seen in the spectra of symbiotic stars. In this work, ultraviolet (UV), optical, and near-infrared observations are presented, aimed at exploring and strengthening the proposed symbiotic classification for this star. Our far-UV 1300–1800 Å spectrum of SU Lyn, obtained with the ASTROSAT mission’s UVIT payload, shows emission lines of Si iv, C iv, O iii, and N iii in a spectrum typical of symbiotic stars. The UV spectrum robustly confirms SU Lyn’s symbiotic nature. The detection of high excitation lines in a high-resolution optical spectrum further consolidates its symbiotic nature. As is being recognized, the potential existence of other similar symbiotic systems could significantly impact the census of symbiotic stars in the Galaxy.

scholarly journals Ultraviolet properties of the symbiotic stars

1982 ◽  
Vol 70 ◽  
pp. 103-113
Author(s):  
Mark H. Slovak ◽  
David L. Lambert
Keyword(s):  
High Resolution ◽  
Broad Band ◽  
Symbiotic Star ◽  
Symbiotic Stars ◽  
Interim Report

Prior to the launch of the IDE satellite in early 1978, the only symbiotic star previously detected in the ultraviolet by earlier UV satellites, such as the 0A0-2, TD-1 and ANS experiments, was AG Pegasi = HD 207757 (Gallager et al. 1979). These broad-band observations indicated that the symbiotics as a class may show a significant ultraviolet flux and thus they became natural candidates for a survey with the IUE satellite. The following is an interim report on a survey of the symbiotics, both at low and, for AG Pegasi and CH Cygni, at high resolution.

Symbiotic Stars in the Local Group of Galaxies: POINT-AGAPE Catalogue Revisited

2017 ◽  
Vol 14 (S339) ◽  
pp. 291-294
Author(s):  
K. Drozd ◽  
J. Mikołajewska ◽  
M. Darnley ◽  
K. Iłkiewicz ◽  
N. Caldwell ◽  
...  
Keyword(s):  
Light Curve ◽  
Local Group ◽  
Light Curves ◽  
Symbiotic Star ◽  
Symbiotic Stars ◽  
Original Point

AbstractThis research was prompted by the discovery of 35 new or candidate symbiotic stars during a targeted search in the Local Group of Galaxies. A catalogue of a further 200 or so such objects has now been compiled. Many of them could be identified with counterparts in the POINT-AGAPE Catalogue. However, information in the Catalogue is limited to position, brightness and possible period, and light-curves are not available. The poster presented an example of a light-curve of a symbiotic star retrieved from original Point-Agape Catalogue data.

scholarly journals The Chromospheric Spectrum and the Atmosphere of 31 Cygni

1957 ◽  
Vol 3 ◽  
pp. 165-172
Author(s):  
A. McKellar ◽  
R. M. Petrie
Keyword(s):  
Ordinary Sense ◽  
Late Type ◽  
Double Stars ◽  
Random Motions ◽  
Type Giant

The binary 31 Cygni is not, in the ordinary sense, an unstable star. Nevertheless, the organizers of this symposium have invited the present paper as a discussion of additional recent evidence of random motions of masses of gas in the atmospheres of the late-type giant components of certain double stars.

Magnesium emission variability among late-type giant stars

1982 ◽  
Vol 253 ◽  
pp. 716 ◽  
Author(s):  
D. J. Mullan ◽  
R. E. Stencel
Keyword(s):  
Late Type ◽  
Giant Stars ◽  
Type Giant

Einstein Observatory magnitude-limited X-ray survey of late-type giant and supergiant stars

1990 ◽  
Vol 348 ◽  
pp. 253 ◽  
Author(s):  
A. Maggio ◽  
G. S. Vaiana ◽  
B. M. Haisch ◽  
R. A. Stern ◽  
J. Bookbinder ◽  
...  
Keyword(s):  
Late Type ◽  
X Ray ◽  
Type Giant ◽  
Einstein Observatory

Possible radio flaring activity on a late-type giant star, Alpha Ceti

1981 ◽  
Vol 245 ◽  
pp. L71 ◽  
Author(s):  
D. C. Boice ◽  
J. R. Kuhn ◽  
R. D. Robinson ◽  
S. P. Worden
Keyword(s):  
Late Type ◽  
Giant Star ◽  
Type Giant

scholarly journals UV and optical spectroscopy of CH Cygni in 1980–86

1987 ◽  
Vol 122 ◽  
pp. 487-489 ◽  
Author(s):  
J. Mikołajewska ◽  
M. Mikołajewski ◽  
R. Biernikowicz ◽  
P.L. Selvelli ◽  
Z. Turło
Keyword(s):  
Emission Line ◽  
Optical Spectroscopy ◽  
Active Phase ◽  
Emission Lines ◽  
Symbiotic Star ◽  
Uv Spectrum ◽  
Brightness Level ◽  
Radio Outburst ◽  
Large Continuum

CH Cyg is a binary (P∼5750 days) consisting of a normal M6-7 giant and an unseen companion. During active phase its spectrum is similar to that of a symbiotic star - the strong B-A continuum and numerous low-excitation emission lines dominate the visual and UV spectrum. The last outburst, started in 1977, is conspicuous by the highest brightness level observed since monitoring begun in 1935. In mid 1984, a drop in brightness was accompanied by large continuum and emission line changes and correlated with a radio outburst and two expanding jets appearance (Taylor et al. 1985).

scholarly journals Symbiotic star UV emission and theoretical models

1982 ◽  
Vol 70 ◽  
pp. 269-272
Author(s):  
M. Kafatos
Keyword(s):  
Line Emission ◽  
Theoretical Models ◽  
Symbiotic Star ◽  
Symbiotic Stars ◽  
Uv Emission

Observations of symbiotic stars in the far UV have provided important information on the nature of these objects. The canonical spectrum of a symbiotic star, e.g. RW Hya, Z And, AG Peg, is dominated by strong allowed and semiforbidden lines of a variety of at least twice ionized elements. Weaker emission from neutral and singly ionized species is also present. The Mg II doublet is usually very strong and may be associated with the M giant primary. A continuum may or may not be present in the 1200 - 2000 A range but is generally present in the range 2000 - 3200 A range, the latter arising from free-free and bound-free emission in the same nebula that is responsible for the UV line emission (CI Cyg, RW Hya, RX Pup). The suspected hot subdwarf continuum is seen in some cases in the range 1200 - 2000 A (RW Hya, AG Peg, SY Mus).

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