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On the outburst amplitude of the soft X-ray transients

T. Shahbaz·E. Kuulkers
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Abstract

We find a strong correlation between the optical outburst amplitude Delta V and orbital period P_{orb} for the soft X-ray transient sources with orbital periods less than 1 day. By fitting the observed values for 8 X-ray transients we determine an empirical relation that can be used to predict the orbital period of an X-ray transient given only its outburst amplitude: ΔV= 14.36 - 7.63\log P_{orb}(h). For periods less than 12 hrs we determine a relation for the absolute magnitude of the accretion disc during outburst, which then allows us to estimate the distances to the sources.

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T. Shahbaz, E. Kuulkers. 1997-10-10. On the outburst amplitude of the soft X-ray transients. https://doi.org/10.1046/j.1365-8711.1998.29511221.x

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