A precise measurement of the orbital period parameters of Cygnus X-3

Abstract

We present X-ray light curves of Cygnus X-3 as measured by the recently launched AstroSat satellite. The light curve folded over the binary period of 4.8 hours shows a remarkable stability over the past 45 years and we find that we can use this information to measure the zero point to better than 100 s. We revisit the historical binary phase measurements and examine the stability of the binary period over 45 years. We present a new binary ephemeris with the period and period derivative determined to an accuracy much better than previously reported. We do not find any evidence for a second derivative in the period variation. The precise binary period measurements, however, indicate a hint of short term episodic variations in periods. Interestingly, these short term period variations coincide with the period of enhanced jet activity exhibited by the source. We discuss the implications of these observations on the nature of the binary system.

arXiv comment8 pages, 7 figures, Accepted for publication in ApJ

References in corpus (14)

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• Disk-Jet Connection in Cygnus X-3
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• Correlated radio:X-ray emission in the hard states of Galactic microquasars

Cited by in corpus (12)

• A catalogue of high-mass X-ray binaries in the Galaxy: from the INTEGRAL to the Gaia era
• A comprehensive study of high-energy gamma-ray and radio emission from Cyg X-3
• The X-ray binary GX 339-4/V821 Ara: the distance, inclination, evolutionary status and mass transfer
• Photoionization Emission Models for the Cyg X-3 X-ray Spectrum
• Multi-scale time- and frequency-domain likelihood analysis with photon weights
• The Period Change and Long-Term Variability of Cyg X-3
• Jets in the soft state in Cyg X-3 caused by advection of the donor magnetic field and unification with low-mass X-ray binaries
• AstroSat observation of GX 5-1: Spectral and timing evolution
• Investigating the mini and giant radio flare episodes of Cygnus X-3
• Science with the $AstroSat$ Soft X-ray Telescope: an overview
• Study of the Cygnus X-3 Microquasar with the RATAN-600 Radio telescope in Multi-Azimuth Observing Mode
• Impact on orbital period of X-ray Binary system attached to a cosmic string