Relaxation of Coulomb States in Semiconductors Probed by FEL Radiation R.Kh. Zhukavin, K.A. Kovalevsky, V.V. Tsyplenkov, S.G. Pavlov, H-W. Hübers, Yu.Yu. Choporova, B.A. Knyazev, J.M. Klopf, B. Redlich, N.V. Abrosimov et al. (2 more) EPJ Web Conf., 195 (2018) 07008 Published online: 23 November 2018 DOI: 10.1051/epjconf/201819507008