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HS0551+7241: A New Possible Magnetic Cataclysmic Variable in the Hamburg/CfA Bright Quasar Survey

D. Dobrzycka·A. Dobrzycki·D. Engels·H. -J. Hagen
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Abstract

We present the analysis of the spectroscopic observations of a newly discovered cataclysmic variable HS0551+7241. In 1995 the star's brightness dropped by Delta(B)~2.5 mag and HS0551+7241 entered a low state lasting for ~2 yr. The H-alpha, H-beta and HeII(4686) emission line radial velocity curves show evidence of short ~50 min fluctuations superimposed on longer, ~4 hour variations. We found similar modulations in the line fluxes and the line equivalent widths. The continuum magnitude light curve suggest that HS0551+7241 may be an eclipsing system. If the 4 hour period is related to the orbital period then the mass function is ~0.138 M_sun. Relatively strong HeII(4686) emission and short fluctuation may suggest that the binary is an intermediate polar. In that case the ~50 min variations would correspond to the Alfven radius of ~3 x 10^10 cm.

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D. Dobrzycka, A. Dobrzycki, D. Engels, H. -J. Hagen. 1998-01-12. HS0551+7241: A New Possible Magnetic Cataclysmic Variable in the Hamburg/CfA Bright Quasar Survey. https://doi.org/10.1086/300281

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