The active chromosphere binary HD 17433 (VY Arietis)
The sixth-magnitude K star HD 17433 (VY Ari) is shown to be an active-chromosphere binary with an orbital period of 13.198 days. A photometric (rotational) period of 17.4 days is indicated by the existing photometry, implying that HD 17433 is not in synchronous rotation. In the optical, H-alpha is seen in emission, with variable profile and intensity; He I lambda-5876 is present in absorption. IUE observations show chromospheric and transition-region emission lines with surface fluxes up to 200 times greater than those observed in the quiet sun. The luminosity and radius are appropriate for a subgiant, and the kinematics suggest Pleiades group membership. The presence of a lithium absorption feature indicates it may either be a young object, possibly a pre-main sequence star or an evolved spotted RS CVn system. Interpretations from the optical measurement of the magnetic field strength of HD 17433 are given. 62 refs.
- Research Organization:
- Toledo Univ., OH (USA); Smithsonian Astrophysical Observatory, Cambridge, MA (USA); Joint Institute for Laboratory Astrophysics, Boulder, CO (USA); National Research Council of Canada, Herzberg Institute of Astrophysics, Ottawa
- OSTI ID:
- 5841996
- Journal Information:
- Astrophys. J.; (United States), Vol. 339
- Country of Publication:
- United States
- Language:
- English
Similar Records
Coordinated ultraviolet, optical, and radio observations of HR 1099 and UX Arietis
On the Origin of Sub-subgiant Stars. I. Demographics
Related Subjects
GENERAL PHYSICS
BINARY STARS
STELLAR ACTIVITY
BALMER LINES
EMISSION SPECTRA
LITHIUM
LUMINOSITY
MAGNETIC FLUX
MAGNETIC STARS
ORBITS
PHOTOMETRY
RADIAL VELOCITY
ROTATION
SIZE
STELLAR ATMOSPHERES
ULTRAVIOLET SPECTRA
ALKALI METALS
ATMOSPHERES
ELEMENTS
METALS
MOTION
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
SPECTRA
STARS
VELOCITY
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
Radio & X-Ray Sources