Low-temperature x-ray magnetic circular dichroism measurements on the endohedral single-molecule magnet DySc2N@C-80 at the Dy M-4,M-5 edges reveal a shrinking of the opening of the observed hysteresis with increasing x-ray flux. Time-dependent measurements show that the exposure of the molecules to x-rays resonant with the Dy M-5 edge accelerates the relaxation of magnetization more than off-resonant x-rays. The results cannot be explained by a homogeneous temperature rise due to x-ray absorption. Moreover, the observed large demagnetization cross sections indicate that the resonant absorption of one x-ray photon induces the demagnetization of many molecules. (c) 2014 AIP Publishing LLC.