Further Evolution of V 1016 Cygni, 1974-77

Ciatti, F.; Mammano, A.; Vittone, A. A.

doi:10.1017/s0252921100080313

Cited by 10 publications

(18 citation statements)

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“…a Herbig Be star accreting material from a disk (Thompson et al 1977); 2. an evolved B[e] supergiant surrounded by an excretion disk (Hartmann et al 1980); 3. a young planetary nebula (Ciatti et al 1974). …”

Section: Possible Nature Of Mwc 349amentioning

confidence: 99%

Bispectrum speckle interferometry of the B[e] star MWC 349A

Hofmann

Balega

Ikhsanov

et al. 2002

A&A

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Abstract. We present the results of bispectrum speckle interferometry of the B[e] star MWC 349A obtained with the SAO 6 m telescope. Our diffraction-limited J-, H-, and K-band images (resolutions 43-74 mas) suggest the star is surrounded by a circumstellar disk seen almost edge-on. The observed visibility shape is consistent with a two-component elliptical disk model, probably corresponding to the gaseous and dusty components of the disk. We show that the classification of the object as a pre-main-sequence star or a young planetary nebula is problematic. An analysis of the uncertainties in the basic parameter determination leads us to the conclusion that MWC 349A is probably either a B[e] supergiant or a binary system, in which the B[e]-companion dominates the observed properties.

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Section: Possible Nature Of Mwc 349amentioning

confidence: 99%

Bispectrum speckle interferometry of the B[e] star MWC 349A

Hofmann

Balega

Ikhsanov

et al. 2002

A&A

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“…In the 1970s, several authors (Geisel 1970;Ciatti et al 1974;Allen & Swings 1972, 1976 noticed that a peculiar group of Be stars showed forbidden emission lines together with a strong infrared excess. Members of this group were later referred as "B[e] stars" (see e.g.…”

Section: Introductionmentioning

confidence: 99%

First detections of FS Canis Majoris stars in clusters

Fuente

Najarro

Trombley

et al. 2015

A&A

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Context. FS CMa stars are low-luminosity objects showing the B[e] phenomenon whose evolutionary state remains a puzzle. These stars are surrounded by compact disks of warm dust of unknown origin. Hitherto, membership of FS CMa stars to coeval populations has never been confirmed. Aims. The discovery of low-luminosity line emitters in the young massive clusters Mercer 20 and Mercer 70 prompts us to investigate the nature of such objects. We intend to confirm membership to coeval populations in order to characterize these emission-line stars through the cluster properties.

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“…Several attempts were made to classify peculiar Be stars in homogeneous groups. Wackerling (1970) indicated a variety of hot stars with abnormal spectra as BQ, and additionally those with forbidden lines were classified as BQ[ ] (Ciatti et al 1974). Stars with characteristics such as HD 45677, were named B[e] stars (Allen & Swings 1976) referring to the presence of forbidden lines, e.g.…”

Section: Introductionmentioning

confidence: 99%

“…Another suggestion for the infrared excess of HD 45677 is a cool companion. This hypothetical companion has been suggested to be a cool giant (Ciatti et al 1974), or an infrared object similar to the BecklinNeugebauer object (Low et al 1970). Searches for CO (1−0) (Nyman et al 1992), 18 cm OH maser (Le Squeren et al 1992), and SiO maser (Dickinson et al 1978) emission from HD 45677 have been made, but all detections were negative.…”

Section: Introductionmentioning

confidence: 99%

The peculiar B[e] star HD 45677

Winter

Ancker

1997

Astron. Astrophys. Suppl. Ser.

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Abstract. The photometric behaviour of the peculiar B[e] star HD 45677 over the last 25 years is investigated. We conclude that the photometric variations (V = 7.m 22−8. m 85) on such a time scale can be well explained by obscurations, possibly due to large (> 1 µm) circumstellar (CS) dust grains which were created after an explosive event around 1950. Intermediate time scale variations are also identified and can be well explained by infall of CS material.Evidence is also found for smaller, pulse-like, amplitude variations. The time scale of this "flickering" ranges from days down to hours and is explained by instabilities in accretion flows towards HD 45677. The accretion mechanisms can be the origin of the hypothesized existence of a bipolar flow.HD 45677, seen edge-on, shows evidence for the presence of a circumstellar disk. The significant accretion flows in this disk probably increased some time after the 1950 event, either due to a fall-back of part of the ejected material by a blow-out around 1950 or either due to the explosive dissociation of a large cometary-like body. Dynamic effects of such infalling and outflowing material close to the stellar surface are also detected by high resolution spectroscopy in the Hα and He i profiles. These short time scale variations are also seen in the cool material as detected by the variations in the violet part of the Na i D profiles, which are probably due to collisions of the outflowing material with the outer disk.The presence of a disk is often indicated and here by the emission of the sodium lines with a strong absorption component at the systemic velocity (about 20 km s −1 ). Most detected lines, except Hα, are well centered at this velocity. Apart from the red [Sii] lines, all other nebular lines as well as many other emission lines, including the Fe ii emission spectrum, were seen in spectra taken far Send offprint requests to: D. de Winter (dolf@astro1.ft.uam.es) Based on observations collected at the European Southern Observatory, La Silla, Chile, and on data collected in the longterm photometry of variables programme at ESO. before and after the 1950 event as well as in the latest spectra. So, the situation of the gaseous stellar environment seems to be stable in spite of the large photometric variations. The Fe ii emission lines are double peaked with a velocity separation of about 32 km s −1 . This could mean that the inner disk material, in which these lines are thought to be formed, rotates with about 16 km s −1 . In our 1992 data this rotation velocity seems to range up to 30 km s −1 , which could be due to material accelerated by the 1950 event.We discuss in this paper the evolutionary status of HD 45677. Because of its rather isolated position in the sky and because of the very fast evolution of a B2 type star, we think that HD 45677 could be young, but not in the sense of being a pre-main sequence object. Options like an evolved object such as a LBV or PN are not suitable because of the probable luminosity class III, IV or V and its rather cool c...

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Further Evolution of V 1016 Cygni, 1974-77

Cited by 10 publications

References 0 publications

Bispectrum speckle interferometry of the B[e] star MWC 349A

Bispectrum speckle interferometry of the B[e] star MWC 349A

First detections of FS Canis Majoris stars in clusters

The peculiar B[e] star HD 45677

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