Confirmation of the orbital period of Scorpius X-1

Abstract

view Abstract Citations (21) References (30) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Confirmation of the orbital period of Scorpius X-1. LaSala, J. ; Thorstensen, J. R. Abstract Radial velocities of Sco X-1 were measured for eight consecutive days in 1982 in order to confirm that the 0.787313 d photometric period found by Gottleib et al. (1975) is identical with the orbital period. High SNR spectra of Sco X-1, obtained by the McGraw-Hill Observatory 1.3-m reflector, were reduced to emission-line radial velocities. He II 4686-A emissions were highly visible around the orbit, and their base velocities agreed well in phase with those of Crampton et al. (1976), when compared using the precise photometric period of Gottleib et al., indicating that the spectroscopic and photometric periods of 0.787 d are identical. This exact period accurately predicts velocity phase after a lapse of nearly 7 yr, and hence is almost certainly the orbital period. The H-beta line wanders somewhat in phase, which seems to explain the discrepancy between the various results in the literature. Publication: The Astronomical Journal Pub Date: October 1985 DOI: 10.1086/113915 Bibcode: 1985AJ.....90.2077L Keywords: Astronomical Spectroscopy; Binary Stars; Orbit Calculation; Stellar Orbits; X Ray Sources; Emission Spectra; H Beta Line; Periodic Variations; Radial Velocity; Scorpius Constellation; Astronomy full text sources ADS | data products SIMBAD (1)