Gro J1744-28: Last Gasps of a Dying Low-mass X-ray Binary
نویسندگان
چکیده
We argue that the bursting, transient X-ray source GRO J1744-28 is a binary consisting of a very low-mass (M ≈ 0.2M⊙), highly evolved giant star that is transferring mass by Roche lobe overflow onto a high-mass (M ≈ 1.8M⊙) neutron star. We explore a picture in which the bursts are due to thermonuclear flashes in matter that has accreted onto the neutron star. We attribute the unusually hard spectra of the bursts and the high burst rate compared to normal Type I X-ray burst sources – indeed the existence of unstable nuclear burning itself – to the unusually strong surface magnetic field, Bs ≈ 1 × 10 13 G, of the neutron star. Subject headings: Accretion —Magnetic Fields — Stars: Binary: Close — Stars: Evolution — Stars: Neutron — X-rays: Bursts
منابع مشابه
Letter to the Editor Evidence for neutron star formation from accretion induced collapse of a white dwarf
The orbital parameters of the recently discovered transient burster/pulsar GRO J1744–28 indicate that this system is a low-mass X-ray binary in an advanced stage of its mass transfer, with several tenths of a solar mass already transferred from the donor to the compact star. All neutron stars known to have accreted such an amount have very weak magnetic fields, and this has led to the idea that...
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