The X-ray spectrum of the Gamma Bright Quasar S5 0836+710

We present the results of an ASCA observation of the high redshift flat spectrum radio quasar S5 0836+710. The $\sim 0.4-10$ keV X-ray spectrum is remarkably flat with $\Gamma \sim 1.4$ and substantial intrinsic absorption at low energy. The spectral slope was found to be in good agreement with the non--simultaneous ROSAT PSPC observations while no evidence of intrinsic absorption has been found in the PSPC spectrum. Our results suggest time variability of the absorbing material on timescales less than five months in the source rest--frame.