Wind Velocity Variations in the Luminous Blue Variable{endash}Type Erupting Star of the Wolf-Rayet Binary HD 5980

Journal Article · Wed Apr 01 00:00:00 EST 1998 · Astrophysical Journal

DOI:https://doi.org/10.1086/305398· OSTI ID:303881

Koenigsberger, G ^[1]; Auer, L H ^[2]; Georgiev, L ^[1]; Guinan, E ^[3]

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1. Instituto de Astronomia-UNAM, Apdo. Postal 70-264, 04510 (Mexico) D.F.
2. Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545 (United States)
3. Department of Astronomy and Astrophysics, Villanova University, Villanova, Pennsylvania 19085 (United States)

We present the wind velocity and UV luminosity variations in the Wolf-Rayet system HD 5980 obtained over a time span during which one of the stars of the system was transformed into a luminous blue variable and underwent an eruption. We are able to separate the velocity components of the two stars in the system: a stable velocity component at {minus}1700thinspkmthinsps{sup {minus}1} is associated with the nonerupting star, while the variable wind with velocities ranging from {minus}500 to {minus}3000thinspkmthinsps{sup {minus}1} corresponds to the eruptor. The development of a fast wind following the slow wind eruptive phase is observed. Under the assumption of radiatively driven winds, these changing velocities indicate that the radius of the photosphere gradually increased during at least 12 years prior to the 1994 eruption, decreasing rapidly thereafter. An estimate of the stellar parameters indicates that the erupting star is massive ({ital M} {gt} 40 {ital M}{sub {circle_dot}}) and very luminous ({ital L} {gt} 10 {ital L}{sub {circle_dot}}), and that during the eruption its radius extended beyond the binary orbit ({ital R}{sub *} {gt} 100 {ital R}{sub {circle_dot}}). {copyright} {ital {copyright} 1998.} {ital The American Astronomical Society}

• OSTI ID: 303881
• Journal Information: Astrophysical Journal, Vol. 496, Issue 2; Other Information: PBD: Apr 1998
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BINARY STARS
ERUPTIVE VARIABLE STARS
WOLF-RAYET STARS
STELLAR WINDS
MASS TRANSFER
STAR EVOLUTION
TEMPERATURE RANGE
ORBITS
STARS
INDIVIDUAL
HENRY DRAPER NUTBER
HD 5980
STARS
TASS LOSS
ULTRAVIOLET STARS