Observational and theoretical mass-loss rates of O stars in the Magellanic Clouds

Journal Article · Tue Nov 01 04:00:00 EST 1988 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/166866· OSTI ID:6533918

Leitherer, C

The stellar-wind properties of 26 luminous O stars in the Magellanic Clouds are investigated. Observational mass-loss rates (MLRs) are derived from the H-alpha emission in these stars. It is found that MLRs derived from H-alpha and from UV resonance lines agree if the velocity law and carbon- and nitrogen-ionization fractions of the wind are the same as in comparable Galactic stars and if the canonical abundances for the Clouds are adopted. Theoretical and observational MLRs disagree if the stellar parameters associated with a given spectral type are identical in the Galaxy and in the Magellanic Clouds. Due to the extreme sensitivity of a line-driven wind to the stellar luminosity, the MLRs derived theoretically are strongly dependent on the adopted spectral-type/T(eff) calibration. If the T(eff) of SMC stars is hotter by about 10 percent than in Galactic stars of identical spectral type, theoretical and observational MLRs agree. 33 references.

• Research Organization: Joint Institute for Laboratory Astrophysics, Boulder, CO (USA)
• OSTI ID: 6533918
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 334; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102 -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BALMER LINES
COMPARATIVE EVALUATIONS
EMISSION SPECTRA
GALAXIES
IONIZATION
LUMINOSITY
MAGELLANIC CLOUDS
MASS TRANSFER
MILKY WAY
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
SPECTRA
STARS
STELLAR ACTIVITY
STELLAR WINDS
ULTRAVIOLET SPECTRA
VELOCITY