PISTIL, a reactivity modulation device to probe the transfer function of the nuclear reactor CROCUS Yifeng Jiang, Benoit Geslot, Vincent Lamirand, Pierre Leconte, Daniel Godat, Laurent Braun, Pavel Frajtag, Christine Coquelet-Pascal and Andreas Pautz EPJ Web Conf., 253 (2021) 04007 Published online: 19 November 2021 DOI: 10.1051/epjconf/202125304007