The stellar intensity interferometer at Narrabri Observatory has been used, for the first time, to make observations of a multiple star (? Vel). Measurements have been made in the continuum at ?4430 and in the C III–IV emission feature at ?4650. The observations at ?4430 give the angular size of the semi-major axis of the binary system ?2 Vel and the angular diameter of the Wolf–Rayet component, while the observations at ?4650 give the angular size of the extended region responsible for the emission feature. The results have been combined with spectroscopic and photometric data to find the distance of ? Vel, the radius, absolute magnitude and emergent flux (?5460) of the Wolf–Rayet star, and the radius and emergent flux (?4650) of the emission region. The surface gravity and effective temperature of the Wolf–Rayet star have been estimated and the size of the emission region has been found to correspond to the critical Roche equipotential lobe around the Wolf–Rayet star. It is concluded that a stellar intensity interferometer can be applied profitably to the study of close binaries and emission-line stars.
- 1 - natural sciences ; 2 - physics & astronomy ; 3 - astronomy & astrophysics
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- 1 - Physical Sciences ; 2 - Earth and Planetary Sciences ; 3 - Space and Planetary Science
- 1 - Physical Sciences ; 2 - Physics and Astronomy ; 3 - Astronomy and Astrophysics