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During typical high-current Reversed Field Pinch (RFP) discharges, long phases of improved confinement with helical symmetry are occasionally interrupted by magnetic reconnection events, which cause weakening of plasma confinement and consequently significant Plasma-Wall Interaction (PWI)~\cite{Zanca_JNuclMat_2007, Gobbin_NF_2022}. This work aims at determining the role of tearing mode phase-locking in driving PWI in RFX-mod, as captured by a fast camera imaging the graphite-covered inner wall~\cite{Scarin_NF_2019}.
An initial analysis based on a three-dimensional Connection Length map~\cite{Schmitz_NF_2008}, computed using the Hamiltonian guiding-center code \orb~\cite{White_ORBIT}, indicates that $m = 1$ tearing modes play a primary role in shaping the PWI pattern. Moreover, it highlights a previously unreported contribution of the $m = 0$, $n = 7$ mode to the observed PWI~\cite{Agostini_NF_2017, Spizzo_NF_2017}. Connection Length map reproduces the PWI features in detail, suggesting the presence of complex hidden structures in the magnetic topology associated with stocasticity and enhanced particle losses~\cite{Spizzo_CHAOS}. A more refined analysis considering the dynamical properties of Maxwellian ions simulated in \orb~confirms the dual PWI topological nature during the event~\cite{Porcu_PoP}. These results emphasize the need for advanced diagnostic systems and improved control of tearing mode dynamics. The upcoming RFX-mod2 upgrade~\cite{Marchiori_FED_2017, Marconato_FED_2019}, including enhanced magnetic pickup arrays and a system of seven fast cameras, will enable a more precise characterization of these interactions and their relation to tearing modes phase-locking phenomena.
Moreover, the first implementation in \orb~of a three-dimensional electrostatic potential calculated by the three-dimensional MHD code Specyl~\cite{Cappello_Biskamp} is shown to be a fundamental key for understanding the thermal content behavior during magnetic reconnection, which had not been fully disclosed by numerical methods. Such analysis shows that magnetic reconnection events preferabily deplete the thermal content of the plasma and accelerate particle towards the wall~\cite{Spizzo_PPCF_2026}, coherently to what already observed experimentally via the Neutral Particle Analyzer (NPA) diagnostic~\cite{Anderson_PoP_2016}.
The NPA measurements constistute a fundamental instrument to understand the correlation between the onset of magnetic reconnection and the loss of accelerated particles at the plasma edge. This work also includes a preliminary refurbishment activity made on the diagnostic in perspective of the upgraded RFX-mod2~\cite{Marrelli_NF_2019, Carraro_NF_2024}, namely the calibration in time and energy of the acquisition system based on the CAEN 2730 digitizer.
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