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Title: FUSE observations of a full orbit of Scorpius X-1

We obtained UV spectra of X-ray binary Scorpius X-1 in the 900-1200 Å range with the Far Ultraviolet Spectroscopic Explorer over the full 0.79 day binary orbit. The strongest emission lines are the doublet of O VI at 1032,1038 Å and the C III complex at 1175 Å. The spectrum is affected by a multitude of narrow interstellar absorption lines, both atomic and molecular. Examination of line variability and Doppler tomograms suggests emission from both the neighborhood of the donor star and the accretion disk. Models of turbulence and Doppler broadened Keplerian disk lines Doppler shifted with the orbit of the neutron star added to narrow Gaussian emission lines with undetermined Doppler shift fit the data with consistent values of disk radius, inclination, and radial line brightness profile. The Doppler shift of the narrow component with the orbit suggests an association with the donor star. We test our line models with previously analyzed near UV spectra obtained with the Hubble Space Telescope (HST) Goddard High Resolution Spectrograph and archival spectra obtained with the HST Cosmic Origins Spectrograph.
Authors:
 [1] ; ;  [2]
  1. Clayton State University, 2000 Clayton State Boulevard Morrow, GA 30260 (United States)
  2. Smithsonian Astrophysical Observatory, Mail Stop 83 Cambridge, MA 02138 (United States)
Publication Date:
OSTI Identifier:
22364993
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 793; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABSORPTION; ACCRETION DISKS; BINARY STARS; COSMIC X-RAY SOURCES; DATA; DOPPLER EFFECT; EMISSION; FAR ULTRAVIOLET RADIATION; INCLINATION; NEUTRON STARS; NEUTRONS; ORBITS; RESOLUTION; TELESCOPES; TURBULENCE; ULTRAVIOLET SPECTRA; X RADIATION