Speaker
Description
In tokamaks, measuring core electron temperatures becomes challenging at high values (typically >6–7 keV), where discrepancies often arise between diagnostics such as Thomson Scattering and ECE. Yet, accurate temperature measurements are critical for future reactors like ITER, CFETR or DEMO, where core Te is expected to be over 25 keV [1,2,3]. These discrepancies, evident in such high-Te scenarios, highlight not only a diagnostic issue but also an opportunity to deepen our understanding of core plasma physics, and recent studies have provided further insights, yielding more substantial results and clarifying additional aspects [4,5,6].
At the same time, the scientific community requires a larger experimental database to strengthen hypotheses developed in recent years. Data at relevant temperatures are becoming increasingly available as tokamak advancements progress toward reactor-scale conditions. Higher injected power (NBI, ECRH, CRH), longer plasma discharges, and improved diagnostics now enable the construction of an extensive database—more comprehensive than ever before—to investigate the discrepancy systematically using a standardized procedure [7].
To achieve this goal, the entire JET-DTE3 dataset is being analysed, with careful selection of relevant shots. Corrupted shots are excluded, and only discharges with consistent ECE and HRTS measurements are considered (Figure 1).
This contribution aims to provide some preliminary results obtained from the larger database, in the framework of the ITPA activity (ITPA JEX#17 on ‘High Te measurements’) born to compare data collected in different machines around the world, trying to find a full explanation of the discrepancy.
