Does the Mass Accretion Rate Depend On the Radius of the Accreting Star?
نویسندگان
چکیده
In some circumstances, the mass accretion rate Ṁ? onto a compact star may depend not only on external boundary conditions, but also on the radius R? of the star. Writing the dependence as Ṁ? ∝ R ?, we estimate p for transient binary systems in a quiescent state. We use the observed luminosities L of accreting neutron stars (R? ∼ 106 cm) in soft X-ray transients and white dwarfs (R? ∼ 109 cm) in similar cataclysmic variables, and estimate Ṁ? in each system through the relation L ≈ GM?Ṁ?/R?, where M? is the mass of the star. From the available data we infer that p ∼ 0.9 ± 0.5. This radial dependence is consistent with radiatively inefficient accretion flows that either are convective or lose mass via a wind.
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