Tracking magnetic resonances in the effective electron heat diffusivity of ECH plasmas of the TJ-II HeliacD. López-Bruna, T. Estrada, F. Medina, E. de la Luna, J. A. Romero, E. Ascasíbar, F. Castejón and V. I. VargasEPL, 82 6 (2008) 65002DOI: https://doi.org/10.1209/0295-5075/82/65002