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The standard modular Equatorial Port Plug (EPP) in ITER is at its final stage of design. It serves as common platforms for different diagnostics systems which are integrated together in three cassettes called Diagnostic Shielding Module (DSM). The equatorial port #12 will host an EPP with six diagnostics: the Visible-Infrared Camera and the H-α Monitor integrated in DSM #1, the Glow Discharge Wall Conditioning, the Radial X-rays Camera and the Hard X-rays Monitor, installed in DSM #2 and the Core Thomson Scattering in DSM #3. The EPP should not only serve as a diagnostic port, but also it has to provide the necessary shielding to allow for maintenance in port interspace and in port cell. This work is devoted to nuclear analyses performed to assess the nuclear loads and the shielding performance of the system. A very detailed neutronic model of EPP #12 has been developed and integrated in a 40° ITER sector MCNP model (C-model). The implemented model has been used to evaluate the neutron and gamma flux distributions, nuclear heating, radiation induced damage, tritium and helium concentration at the ITER end of life in the port plug area.

The ITER electron cyclotron emission (ECE) diagnostic system has primary roles in providing measurements of the core electron temperature profile and the electron temperature fluctuation associated with the neoclassical tearing modes. The ITER ECE system includes a radial and oblique line-of-sight. Four 43-meter long low-loss transmission lines (TLs) are designed to transmit millimeter wave power in the frequency range of 70–1000 GHz in both X- and O-mode polarization from the port plug to the ECE instrumentation room in the diagnostic building. The measurement instrumentation includes two Fourier transform spectrometer (FTS) systems and two radiometer systems. The Indian Domestic Agency (IN-DA) and United States Domestic Agency share the responsibility. The IN-DA scope excluding instrumentation and control has passed its preliminary design review and is progressing towards the final design review (FDR). In parallel, the diagnostic integration in different areas is ongoing. Several captive components for the TLs have passed FDR and will be manufactured for installation in the tokamak building soon. A peer review meeting has been held on the prototype hot calibration source, and its integration and new thermal analysis in the diagnostic shield module are continuing. A prototype TL is being tested. A prototype polarizing Martin-Puplett type FTS, operating in the frequency range 70–1000 GHz, features an in-vacuo fast scanning mechanism and a cryo-cooled dual-channel THz detector system. Its performance has been assessed in detail against ITER requirements.

The influence of large- and small-scale magnetohydrodynamic (MHD) modes on plasma transport properties has been studied. Poloidal and toroidal reconstruction of large m = 2 modes and their evolution in time have been analysed, as well as their electron temperature profiles and heat transport properties with respect to the background plasma. The confinement is improved within the magnetic island, compared to the background plasma as evidenced by a secondary temperature maximum at the centre of the island. The perpendicular heat diffusivity inside the island is estimated to be of the order of 0.01 m(2) s(-1), which is close to the neoclassical value. By cross-correlation of different electron cyclotron emission (ECE) channels, temperature fluctuations in the presence of MHD modes are investigated. For m = 2 islands, they are found to be different for the X- and the O-points. Evidence of a small mode with higher m number between the g = 1 and 2 radii is given.