Experiments using extreme parameters of the NovoFEL radiation V. V. Kubarev, Ya. V. Getmanov, O. A. Shevchenko, E. N. Chesnokov, P. V. Koshlyakov and L. N. Krasnoperov EPJ Web Conf., 195 (2018) 07004 Published online: 23 November 2018 DOI: 10.1051/epjconf/201819507004