On the outburst amplitude of the soft X-ray transients
نویسنده
چکیده
We find a strong correlation between the optical outburst amplitude ∆V and orbital period Porb 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: ∆V = 14.36− 7.63 logPorb(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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