A cyclical period variation detected in the updated orbital period analysis of TV Columbae

Z. DAI; S.-B. QIAN; E. FERNÁNDEZ-LAJÚS; G. BAUME

ASTROPHYSICS AND SPACE SCIENCE

SPRINGER

Lugar: Dordrecht, The Netherlands; Año: 2010 vol. 330 p. 243 - 248

0004-640X

The two CCD photometries of the intermediate polar TV Columbae are made for obtaining the two updated eclipse timings with high precision. There is an interval time ∼ 17yr since the last mid-eclipse time observed in 1991. Thus, the new mid-eclipse times can offer an opportunity to check the previous orbital ephemerides. A calculation indicates that the orbital ephemeris derived by Augusteijn et al. (1994) should be corrected. Based on the proper linear ephemeris (Hellier 1993), the new orbital period analysis suggests a cyclical period variation in the O-C diagram of TV Columbae. Using Applegate’s mechanism to explain the periodic oscillation in O-C diagram, the required energy is larger than that a M0-type star can afford over a complete variation period ∼ 31:0(±3:0)yr. Thus, the light travel-time effect indicates that the tertiary component in TV Columbae may be a dwarf with a low mass, which is near the mass lower limit ∼ 0:08M⊙ as long as the inclination of the third body high enough.