Electron temperature profiles characterization and eITBs dynamics in the helical states of RFX-mod

Electron temperature profiles in RFX-mod 3D helical plasmas are characterized by a complex dynamics recently investigated thanks to the high time resolution \textit{Te} measurements obtained by double filter technique with a multichord soft-x-ray diagnostic.\footnote{P.Franz et al., Nucl. Fusion 53 (2013) 053011} This study is focused in particular on the characterization of the intermittent behaviour of thermal structures developing in helical states and on the loss of helical topology. A statistical approach reveals that the increase of the magnetic chaos and the partial break of the 3D magnetic configuration usually occur in a phase where the electron temperature gradient is already decreasing. For a deeper understanding of this phenomenology the microtearing perturbations and the pressure driven instabilities, the latter investigated by using the stability COBRA code,\footnote{R. Sanchez et al., Computer Physics Communications 141 (2001) 55--65} are considered in the analysis.