Detection of Periodicity in SiO Maser Intensity and Velocity Shift of the Symbiotic Star CH Cyg

We present observations that show that the symbiotic star CH Cygni recently underwent a strong radio outburst that produced a radio-emitting thermal jet. The jet is two-sided and is expanding lengthwise at an observed rate (end to end) of 1 arcsec/year, corresponding to a transverse velocity of 1100 km∙s−1 in each direction. The electron density on January 22, 1985 exceeded 2 × 106 cm−3, and the mass of the (ionized) gas exceeded [Formula: see text]. The emergence of the jet coincided with a decline in the visual luminosity of [Formula: see text].The data are consistent with a jet produced by supercritical accretion in a binary containing a red giant and a [Formula: see text] white dwarf. The discovery of a jet in such a system provides confirming evidence of the role played by accretion in determining the optical and radio properties of this system. It is also the first expanding jet found to be associated with an evolved stellar object.

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An XMM–Newton observation of the symbiotic star AG Peg: the X-ray emission after the end of its 2015 outburst

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/sty2644 ◽

2018 ◽

Vol 481 (4) ◽

pp. 5156-5162

Author(s):

Svetozar A Zhekov ◽

Toma V Tomov

Keyword(s):

Symbiotic Star ◽

X Ray

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Recurrent Novae — A Review

Acta Polytechnica CTU Proceedings ◽

10.14311/app.2015.02.0246 ◽

2015 ◽

Vol 2 (1) ◽

pp. 246-251 ◽

Cited By ~ 2

Author(s):

K. Mukai

Keyword(s):

Accretion Rate ◽

Current Understanding ◽

X Rays ◽

Symbiotic Star ◽

Classical Novae ◽

Extensive Data ◽

Star Evolution ◽

Wide Range ◽

Multi Wavelength ◽

Recurrent Nova

In recent years, recurrent nova eruptions are often observed very intensely in wide range of wavelengths from radio to optical to X-rays. Here I present selected highlights from recent multi-wavelength observations. The enigma of T Pyx is at the heart of this paper. While our current understanding of CV and symbiotic star evolution can explain why certain subset of recurrent novae have high accretion rate, that of T Pyx must be greatly elevated compared to the evolutionary mean. At the same time, we have extensive data to be able to estimate how the nova envelope was ejected in T Pyx, and it turns to be a rather complex tale. One suspects that envelope ejection in recurrent and classical novae in general is more complicated than the textbook descriptions. At the end of the review, I will speculate that these two may be connected.

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A new carbon-symbiotic star in the Large Magellanic Cloud

Publications of the Astronomical Society of the Pacific ◽

10.1086/132552 ◽

1989 ◽

Vol 101 ◽

pp. 917 ◽

Cited By ~ 2

Author(s):

A. P. Cowley ◽

F. D. A. Hartwick

Keyword(s):

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Symbiotic Star

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Observations of the symbiotic star AS 296

Publications of the Astronomical Society of the Pacific ◽

10.1086/132622 ◽

1990 ◽

Vol 102 ◽

pp. 157 ◽

Cited By ~ 1

Author(s):

A. Gutierrez-Moreno ◽

H. Moreno

Keyword(s):

Symbiotic Star

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Characterization of laser Doppler vibrometers using acousto-optic modulators

ACTA IMEKO ◽

10.21014/acta_imeko.v9i5.1001 ◽

2020 ◽

Vol 9 (5) ◽

pp. 361

Author(s):

Michael Gaitan ◽

Jon Geist ◽

Benjamin J. Reschovsky ◽

Ako Chijioke

Keyword(s):

Frequency Shift ◽

Excitation Frequency ◽

Laser Doppler Vibrometer ◽

Laser Doppler ◽

New Approach ◽

Frequency Reference ◽

Discrete Velocity ◽

Velocity Shift ◽

Vibration Excitation

We report on a new approach to characterize the performance of a laser Doppler vibrometer (LDV). The method uses two acousto-optic modulators (AOMs) to frequency shift the light from an LDV by a known quantity to create a synthetic velocity shift that is traceable to a frequency reference. Results are presented for discrete velocity shifts and for sinusoidal velocity shifts that would be equivalent to what would be observed in an ideal accelerometer vibration calibration. The method also enables the user to sweep the synthetic vibration excitation frequency to characterize the bandwidth of an LDV together with its associated electronics.

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