An optimized B/Ir supermirror for Einstein Probe focusing mirrors in x-ray region of above 8 keV

The Einstein Probe (EP) focusing mirrors is a main load to focus and image x-rays. A single-layer which adopts Nickel substrates and Gold reflective coatings has been used for the EP focusing mirrors and has excellent performance below 8 keV. It is a possibility to enhance the effective area of higher x-ray regions by using the multilayer design. The multilayer with single block is designed and has excellent reflectance at specific x-ray energies above 8 keV. 54 multilayers are used for all mirror shells with different incident angles. The optimized B/Ir supermirror design for focusing mirrors with short focal length shows an effective area of up to 152 cm 2 in 9 keV. And, the method can be used to design supermirror for higher x-ray regions, which will achieve hard x-ray detection with short focal length focusing mirrors and small hard x-ray detection satellite.