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Register a new userA spectroscopic, photometric, polarimetric and radio study of the eclipsing polar UZ Fornacis: the first simultaneous SALT and MeerKAT observations
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Zwidofhelangani Khangale Mr
Publication date
2020
fields
Physics
and research's language is
English
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We present phase-resolved spectroscopy, photometry and circular spectropolarimetry of the eclipsing polar UZ Fornacis. Doppler tomography of the strongest emission lines using the inside-out projection revealed the presence of three emission regions: from the irradiated face of the secondary star, the ballistic stream and the threading region, and the magnetically confined accretion stream. The total intensity spectrum shows broad emission features and a continuum that rises in the blue. The circularly polarized spectrum shows the presence of three cyclotron emission harmonics at $sim$4500 AA{}, 6000 AA{} and 7700 AA{}, corresponding to harmonic numbers 4, 3, and 2, respectively. These features are dominant before the eclipse and disappear after the eclipse. The harmonics are consistent with a magnetic field strength of $sim$57 MG. We also present phase-resolved circular and linear photopolarimetry to complement the spectropolarimetry around the times of eclipse. MeerKAT radio observations show a faint source which has a peak flux density of 30.7 $pm$ 5.4 $mu$Jy/beam at 1.28 GHz at the position of UZ For.
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