The period of V444 Cygni and its rate of change

Journal Article · Sun Jul 01 04:00:00 EDT 1990 · Publications of the Astronomical Society of the Pacific; (USA)

DOI:https://doi.org/10.1086/132698· OSTI ID:6592941

Underhill, A B; Grieve, G R; Louth, H ^[1]

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1. British Columbia Univ., Vancouver (Canada) Louth Observatory, Sedro Wooley, WA (USA)

The relation between rate of period change and the rate of mass loss for the Wolf-Rayet star V444 Cyg is examined. The period and rate of period change for V444 Cygni are calculated. Times of primary minima collected from 1940 to 1989 and radial velocity observations are analyzed to calculate these values. The period for V444 Cyg is estimated as 4.2124477 + or - 0.0000009 days and the rate of period change is (2.667 + or - 0.035) x 10 to the -9th day per day. The rate of mass loss is determined by converting the rate of period change using the outflow in a spherical wind expression of Khaliullin (1974). The calculated mass loss rate = 5.6 x 10 to the -6th solar masses/yr with an uncertainty of 13 to 25 percent. 15 refs.

• OSTI ID: 6592941
• Journal Information: Publications of the Astronomical Society of the Pacific; (USA), Journal Name: Publications of the Astronomical Society of the Pacific; (USA) Vol. 102; ISSN PASPA; ISSN 0004-6280
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BINARY STARS
ECLIPSE
MAIN SEQUENCE STARS
MASS TRANSFER
ORBITS
RADIAL VELOCITY
SPECTROPHOTOMETRY
STARS
VARIATIONS
VELOCITY
WOLF-RAYET STARS