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 F _ { X } ( 1–10 keV ) = 4.7 \times 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 \pm 0.2 and hydrogen column density of N _ { H } = 1.0 ^ { +0.4 } _ { -0.3 } \times 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 .