Observations of Eddington-limited type-I X-ray bursts from 4U 1812-12

M. Cocchi; A. Bazzano; L. Natalucci; P. Ubertini; J. Heise; E. Kuulkers; J. M. Muller; J. J. M. in 't Zand

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Observations of Eddington-limited type-I X-ray bursts from 4U 1812-12

M. Cocchi·A. Bazzano·L. Natalucci·P. Ubertini·J. Heise·E. Kuulkers·J. M. Muller·J. J. M. in 't Zand

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Abstract

During more than 3 years (August 1996-October 1999) monitoring of a 40x40 degree sky region around the Galactic Centre by the Wide Field Cameras on board BeppoSAX, a total of 8 type-I bursts have been detected from a sky position consistent with that of 4U 1812-12, a likely neutron-star low-mass X-ray binary. We present the results of a detailed study of the bursts of 4U 1812-12, about 15 years after the last reported observations of X-ray bursts from this source (Murakami et al. 1983). Clear evidence for photospheric radius expansion due to Eddington-limited burst luminosity is present in most of the observed events, allowing an accurate estimate of the source distance (~4 kpc) and its burst parameters.

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M. Cocchi, A. Bazzano, L. Natalucci, P. Ubertini, J. Heise, E. Kuulkers, J. M. Muller, J. J. M. in 't Zand. 2000-03-10. Observations of Eddington-limited type-I X-ray bursts from 4U 1812-12. https://arxiv.org/abs/astro-ph/0003151

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