2018 schedule

Sat 14:00-14:30
Mercure Conservatory

Photometry, spectroscopy and radial velocities of the near contact binary V0775 Cen and the contact binary TW Cru

David J. W. Moriarty


Photometric and spectroscopic analyses of V0775 Cen, a near contact binary with a period of 16 hours and TW Cru, a contact binary with a period of 9 h, indicate both are triple systems. The V0775 Cen spectra are consistent with catalogue values of F0 IV for the primary component; its mass is 1.6 solar and radius 1.7 solar. The effective temperature of the secondary star indicates it has a spectral type of about K4, and its mass is 0.5 solar, yet with a radius of 1.1 solar, it has evolved well past terminal age main sequence. Episodes of emission in the H Balmer and metal lines of TW Cru confirm the conclusion from previously published photometric studies that it is chromospherically active.