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Long-term X-ray variability of the microquasar system LS 5039/RX J1826.2-1450

P. Reig·M. Ribo·J. M. Paredes·J. Marti
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Abstract

We report on the results of the spectral and timing analysis of a BeppoSAX observation of the microquasar system LS 5039/RX J1826.2-1450. The source was found in a low-flux state with Fx(1-10 keV)= 4.7 x 10^{-12} erg cm^{-2} s^{-1}, which represents almost one order of magnitude lower than a previous RXTE observation 2.5 years before. The 0.1--10 keV spectrum is described by an absorbed power-law continuum with photon-number spectral index Gamma=1.8+-0.2 and hydrogen column density of NH=1.0^{+0.4}_{-0.3} x 10^{22} cm^{-2}. According to the orbital parameters of the system the BeppoSAX observation covers the time of an X-ray eclipse should one occur. However, the 1.6-10 keV light curve does not show evidence for such an event, which allows us to give an upper limit to the inclination of the system. The low X-ray flux detected during this observation is interpreted as a decrease in the mass accretion rate onto the compact object due to a decrease in the mass-loss rate from the primary.

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P. Reig, M. Ribo, J. M. Paredes, J. Marti. 2003-04-18. Long-term X-ray variability of the microquasar system LS 5039/RX J1826.2-1450. https://doi.org/10.1051/0004-6361%3A20030674

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