Insight-HXMT, NuSTAR, and INTEGRAL Data Show Disk Truncation in the Hard State of the Black Hole X-Ray Binary MAXI J1820+070

We study X-ray and soft gamma-ray spectra from the hard state of accreting black-hole binary MAXI J1820+070. perform analysis joint HXMT, NuSTAR INTEGRAL. find an overall agreement between all three satellites. Satisfactory fits to data require substantial spectral complexity, with our models including two Comptonization regions their associated disk reflection, a blackbody narrow Fe K$\alpha$ line. Our confirm presence truncation reflecting optically-thick at least $>$10 gravitational radii. However, we that HXMT alone cannot significantly constrain inner