Using neutron stars and black holes in X-ray binaries to probe strong gravitational fields

Science

Volumn 276, Issue 5317, 1997, Pages 1386-1391

  Kaaret, Philip ^a   Ford, Eric C ^a  

^a Columbia University ^*  (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ION;

ARTICLE; ASTRONOMY; ELECTRON; GRAVITY; INFRARED RADIATION; LIGHT; LUMINANCE; MAGNETIC FIELD; NUCLEAR ENERGY; OSCILLATION; PHOTOMETRY; PHOTON; PREDICTION; PRIORITY JOURNAL; RADIATION; SPECTROSCOPY; THEORY; X RAY;

EID: 0030911472     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.276.5317.1386     Document Type: Article

References (73)

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67. It has been suggested that storage of material in the disk is required to produce bright x-ray transients. For a recent review, see (43).
68. Centrifugal force may reduce accretion onto neutron stars when the mass accretion rate is low and the magnetospheric radius is large; this is the "propeller effect" [A. F. Illarionov and R. A. Sunyaev, Sov. Astron. Lett. 1, 73 (1975)]. The importance of the propeller effect is uncertain, in part due to our lack of knowledge of the spin rates of neutron stars in x-ray binaries. These spin rates are currently being determined through QPO observations as described in the previous sections.
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70. E is higher for more massive stars. The quiescent mass accretion rates may differ because of the differing mass ratios of neutron stars versus black hole systems or because of irradiation of the companion in neutron star systems [see M. Ruderman et al., Astrophys. J. 343, 292 (1989) and J. M. Hameury et al., Astron. Astrophys. 277, 81 (1993)].
71. E is higher for more massive stars. The quiescent mass accretion rates may differ because of the differing mass ratios of neutron stars versus black hole systems or because of irradiation of the companion in neutron star systems [see M. Ruderman et al., Astrophys. J. 343, 292 (1989) and J. M. Hameury et al., Astron. Astrophys. 277, 81 (1993)].
72. The accretion rates estimated in (53) use the x-ray luminosity and assume the validity of the ADAF model. These estimates are not suitable for a model-independent evaluation of the radiative efficiency.
73. We thank T. Strohmayer for supplying Fig. 2, M. C. Miller and R. Narayan for communicating results before publication, and K. Chen for useful discussions.