The Dalian Coherent Light Source Center around Xuemin YANG prepared the arguably world’s brightest vaccum UV FEL light in an energy range from 8 to 24 eV, making it unique of the same kind that only operates in the VUV region, By applying the undulator tapering technology in the HGHG mode, a photon flux of 1.4×1014 photons per pulse was achieved.

CAS news release, January 16, 2017