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arXiv · 1305.1393

Spectroscopy of the mysterious Be system FF Cam

T. Garrel·A. S. Miroshnichenko·S. Danford·S. Charbonnel·F. Houpert·K. N. Grankin·A. V. Kusakin
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Abstract

FF Cam is a variable star near the North celestial pole with hydrogen lines in emission. Its optical variability of ~0.3 mag was discovered by HIPPARCOS. The spectral type assigned to the star in SIMBAD is B9, but its position coincides with a ROSAT X-ray source. This suggests the presence of a high-temperature region in the system that could originate at or near a companion object. We undertook a spectroscopic monitoring of FF Cam since the beginning of 2012 and found an extremely variable H-alpha line profile as well as periodically variable radial velocities of numerous absorption lines. The main conclusion from our study is that FF Cam is a binary system with an orbital period of 7.785 days, a B-type primary and a K-type secondary component. We discuss the spectral features, their variations, and the nature of FF Cam.

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T. Garrel, A. S. Miroshnichenko, S. Danford, S. Charbonnel, F. Houpert, K. N. Grankin, A. V. Kusakin. 2013-05-07. Spectroscopy of the mysterious Be system FF Cam. https://arxiv.org/abs/1305.1393

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