EUVE Observations of Epsilon CMa

Previous abstract Next abstract

Session 38 -- EUVE -- Astronomy II
Oral presentation, Tuesday, 2:00-6:30, Zellerbach Auditorium Room

[38.04] EUVE Observations of Epsilon CMa

J. P. Cassinelli (U. Wisc.)

The brightest EUV source in the sky in the long wavelength spectrometer band of EUVE is the B2 II star Epsilon CMa. The star is also detected in the short and medium wavelength spectral bands and several emission lines from Fe and from He II are present. These provide exciting new information regarding the shocked wind of the star. A strong stellar continuum flux is present throughout the long wavelength band from about 400 to 700~\AA, with a continuum jump due to the ionization of He I near 504~\AA. The jump contains information about the very small interstellar attenuation that is present along the 187 parsecs towards this star, as well as about the confluence of lines just longward of the jump. The observations are used in conjunction with angular diameter and UV data on this star to derive $T_{eff}$ and other fundamental atmospheric parameters. Basic results from fits of the observations to model atmospheres and stellar winds are presented in the talk, and reference is made to the related posters by members of our group of investigators: J. MacFarlane, D. Cohen at U. Wisc; J. Vallerga, B. Welsh, P. Vedder at CEA; and J. Drew and M. Hoare at the U. of Oxford.

Tuesday program listing