A Revised Ephemeris and FUSE Observations of the Supersoft X-ray Source CAL 83

Abstract

A new ephemeris has been determined for the supersoft X-ray binary CAL 83 using MACHO photometry. With an improved orbital period of 1.047568 days, it is now possible to phase together photometric and spectroscopic data obtained over the past two decades with new far ultraviolet spectra taken with FUSE. We discuss the properties of the orbital and longterm optical light curves as well as the colors of CAL 83. In the far ultraviolet the only well-detected stellar feature is emission from the O VI resonance doublet. The radial velocity of this emission appears to differ from that of HeII in the optical region, although we only have partial phase coverage for the O VI line. The FUSE continuum variations are similar to the optical light curve in phase and amplitude.

arXiv comment21 pages and 7 figures

References in corpus (8)

• Overview of the Far Ultraviolet Spectroscopic Explorer Mission
• Calibration of the MACHO Photometry Database
• Chandra Discovery of Luminous Supersoft X-Ray Sources in M81
• Six supersoft X-ray binaries: system parameters and twin-jet outflows
• A Luminous Recurrent Supersoft X-ray Source in NGC 300
• X-Ray Off States and Optical Variability in CAL 83
• Catalog of Luminous Supersoft X-ray Sources
• The X-ray off-state of the supersoft source CAL 83 and its interpretation

Cited by in corpus (5)

• Short-period X-ray oscillations in super-soft novae and persistent SSS
• X-ray Pulsations in the Supersoft X-ray Binary CAL 83
• Multiwavelength modeling the SED of Luminous Supersoft X-ray Sources in Large Magellanic Cloud and Small Magellanic Cloud
• Revisiting multiwavelength data on the supersoft X-ray source CAL 83
• The significant contribution of supersoft X-ray Sources to the nebular HeII line emission