Search Publications

Time series photometric spot modelling V. Phase coherence of spots on UZ Librae

Strassmeier, K. G.; Granzer, T.; Oláh, K.

We present spot models for nine years of continuous VI_C photometry of UZ Lib from 1993-2001. The relatively stable double-humped light curve shape suggests extreme phase coherence. From the spot-modelling analysis, we found that the major spots or spot groups are always located on the hemisphere facing the secondary star and exactly in the opposi…

Radial velocities of population II binary stars. I.

Bartkevicius, A.; Sperauskas, J.

Radial velocities for 114 Hipparcos stars, mostly high transverse velocity binaries without previous radial velocity measurements, are published. Measurements are made with the CORAVEL-type radial velocity spectrometer. The accuracy of measurements is better than 1 km/s. Two stars, BD +30 deg 2129A and HD 117466AB are found to be radial velocity v…

On stellar encounters and their effect on cometary orbits in the Oort cloud

Grothues, H. -G.; Serafin, R. A.

We systematically investigate the encounters between the Sun and neighbouring stars and their effects on cometary orbits in the Oort cloud, including the intrinsic one with the star Gl 710 (HIP 89 825), with some implications to stellar and cometary dynamics. Our approach is principally based on the combination of a Keplerian-rectilinear model of …