Multiwavelength observations of EXO 0748-676. II. Emission-line behavior

作者：Pearson K J^*; Hynes R I; Steeghs D; Jonker P G; Haswell C A; King A R; O'Brien K; Nelemans G; Mendez M

来源：Astrophysical Journal, 2006, 648(2): 1169-1180.

DOI：10.1086/506191

• accretion
• accretion disks
• binaries : closestars : individual ( UY Vol)

We present optical and ultraviolet spectra, light curves, and Doppler tomograms of the low-mass X-ray binary EXO 0748 - 676. Using an extensive set of 15 emission-line tomograms, we show that, along with the usual emission from the stream and "hot spot,'' there is extended nonaxisymmetric emission from the disk rim. Some of the emission and H alpha and H beta absorption features lend weight to the hypothesis that part of the stream overflows the disk rim and forms a two phase medium. The data are consistent with a 1.35 M-circle dot neutron star with a main-sequence companion and hence a mass ratio q approximate to 0.34.

• 出版日期2006-9-10