2008A&A...477..853C -
Astronomy and Astrophysics, volume 477853-863 (2008/1-3)
VLBA SiO observations of bright O-rich AGB stars.
COTTON W.D., PERRIN G. and LOPEZ B.
Abstract (from CDS):
We present the results of observations of the SiO masers at 7 mm wavelength in several oxygen rich Asymptotic Giant Branch (AGB) stars. These observations were coordinated with observations using the ESO VLTI/MIDI interferometer at 10µm wavelength. These stars are {omi} Ceti (Mira), U Herculis (U Her), OH26.5+0.6, R Leonis (R Leo), and W Hydrae (W Hya). Both total intensity and linear polarizations are imaged. Linear radial features seen in {omi} Ceti may be associated with an X-ray flare seen a year earlier by Karovska et al. (
2005ApJ...623L.137K). Similar linear features are also seen in R Leo, U Her and OH26.5+0.6. These features typically show systematic radial velocity variations and a tendency for the linear polarization to be perpendicular to the direction of elongation, suggesting that magnetic fields are dynamically important. A wide radial extent of the maser rings observed in U Herculis and OH26.5+0.6 is interpreted as meaning that the outer boundaries of the masing regions in these stars are not truncated by the condensation of SiO onto dust grains.
Abstract Copyright:
∼
Journal keyword(s):
stars: atmospheres - stars: AGB and post-AGB - stars: variables: general - radio lines: stars - masers
Simbad objects:
12
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2008A&A...477..853C and select 'bookmark this link' or equivalent in the popup menu