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A New View of the Supersoft X-Ray Source Cal 87 Observed with XMM-Newton

Marina Orio·Ken Ebisawa·John Heise·Wouter Hartmann
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Abstract

Cal 87 was observed with XMM-Newton in April of 2003. The source shows a rich emission line spectrum, where lines can be identified if they are red-shifted by 700-1200 km/s. These lines seem to have been emitted in a wind from the system. The eclipse is observed to be shifted in phase by 0.03 phi(orb), where phi(orb) is the phase of the optical light curve.

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Marina Orio, Ken Ebisawa, John Heise, Wouter Hartmann. 2004-02-02. A New View of the Supersoft X-Ray Source Cal 87 Observed with XMM-Newton. https://arxiv.org/abs/astro-ph/0402040

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