Browsing by Author "Augusteijn, T"

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    Cataclysmic variables from the Calan-Tololo Survey - I. Photometric periods
    (2004) Tappert, C; Augusteijn, T; Maza, J
    In a search for cataclysmic variables in the Calan-Tololo Survey, we have detected 21 systems, 16 of them previously unknown. In this paper we present detailed time-series photometry for those six confirmed cataclysmic variables that show periodic variability in their light curves. Four of them turned out to be eclipsing systems, while the remaining two show a modulation consisting of two humps. All derived periods are below or, in one case, just at the lower edge of the period gap.
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    Photopolarimetric observations of the new eclipsing polar CTCV J1928-5001
    (2005) Potter, SB; Augusteijn, T; Tappert, C
    We report photopolarimetric observations of a new eclipsing polar (AM Herculis system) discovered in the Calan-Tololo survey. The photometry and polarimetry are modulated on a period of similar to 101 min. Circular polarization variations are seen from similar to-8 to +12 per cent and from similar to 0 to 5 per cent in the red and blue parts of the optical spectrum, respectively. Two linearly polarized pulses are detected at orbital phases coinciding with the reversals in the circular polarization. This is consistent with a magnetic field strength of similar to 20 MG for the white dwarf primary, where accretion takes place at two regions. Both the accretion regions are self-occulted by the white dwarf during parts of the orbit. We estimate some of the system's parameters from its eclipses, which we further refine by modelling the polarimetric observations.