New spectra of the ? CMa variable ? Lupi taken in 1965 show an outflow of hydrogen relative to He I and metal lines in nearly all phases. This outflow, however, is found to be smaller by a factor of 3 than the reported outflow in 1960. Furthermore, the velocity amplitude has decreased to about 16 km/s. The velocity of ? Cen varies with a very short period of between 3 and $3\frac12$ hours (with the amplitude varying between 10 and 20 km/s) as well as with one which may be more than a year. Together with the spectral type (B2 II) this suggests a ? CMa star in a binary system. The extreme width of the spectral lines is unusual for a ? CMa star, and the period is very short for a ? CMa star. It is postulated that ? Cen is intermediate in type between the usual ? CMa variables and ‘normal’ B stars.
- 1 - natural sciences ; 2 - physics & astronomy ; 3 - astronomy & astrophysics
- 1 - sciences appliquees, technologies et medecines ; 2 - sciences biologiques et medicales ; 3 - sciences biologiques fondamentales et appliquees. psychologie
- 1 - Physical Sciences ; 2 - Earth and Planetary Sciences ; 3 - Space and Planetary Science
- 1 - Physical Sciences ; 2 - Physics and Astronomy ; 3 - Astronomy and Astrophysics