Periodicity of the radial-velocity and brightness variations of the hypergiant P Cygni (B1 Ia+), and origin of the shell ejections

Details Periodicity of the radial-velocity and brightness variations of the hypergiant P Cygni (B1 Ia+), and origin of the shell ejections Periodicity of the radial-velocity and brightness variations of the hypergiant P Cygni (B1 Ia+), and origin of the shell ejections

Apr 1986

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1986a%26a...158..335v&link_type=abstract

Astronomy and Astrophysics (ISSN 0004-6361), vol. 158, no. 1-2, April 1986, p. 335-350.

Astronomy and Astrophysics

Astrophysics

32

Brightness Distribution, Radial Velocity, Stellar Envelopes, Stellar Mass Ejection, Supergiant Stars, Balmer Series, Cygnus Constellation, Periodic Variations, Polarimetry, Radiation Pressure, Spectral Energy Distribution, Spectrum Analysis, Stellar Oscillations, Ultraviolet Spectra

Scientific paper

A reanalysis of published radial-velocity measurements of the shell components of P Cyg shows that the variations are not due to periodic oscillations but to shell ejections with a characteristic timescale of about 50 to 100 days. A reanalysis of the photometric variations of P Cyg shows that most of the periodicities claimed in the literature (ranging from 0.5 days to 18 years) are not real. The photometric variations of P Cyg are not strictly periodic, but show a possible range of timescales from 25 to 60 days. The polarization measurements suggest non-periodic variations on timescales of 125 and possibly 12 days. The mean characteristic timescale of about 50 days agrees (within the uncertainty of a factor 2) with the expected timescale for non-radial pulsations of 28 ± 1610 days, as found from the empirical relation between P and Q for normal supergiants. The qualitative agreement between the pulsational time scale and the time scale for the shell ejections suggests that the shells are triggered by non-radial pulsations of the star. The comparison between the acceleration of the shells observed in the Balmer lines with those observed in the UV shows that the acceleration of shells is anticorrelated with their density, suggesting that the shells are aceelerated by radiation pressure of optically thick lines.

Affiliated with

Also associated with

No associations

Rating

Periodicity of the radial-velocity and brightness variations of the hypergiant P Cygni (B1 Ia+), and origin of the shell ejections does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Periodicity of the radial-velocity and brightness variations of the hypergiant P Cygni (B1 Ia+), and origin of the shell ejections, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Periodicity of the radial-velocity and brightness variations of the hypergiant P Cygni (B1 Ia+), and origin of the shell ejections will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1101101