3-5 October 2018
INFN-LNF, Italy
Europe/Rome timezone

Diagnostic of fast-ion energy spectra and densities in magnetized plasmas

3 Oct 2018, 17:05
30m
Bruno Touschek Auditorium (INFN-LNF, Italy)

Bruno Touschek Auditorium

INFN-LNF, Italy

Via E. Fermi, 40 I-00044 Frascati

Speaker

Dr Mirko Salewski (Technical University of Denmark)

Description

The measurement of the energy spectra and densities of alpha-particles and other fast ions are part of the ITER measurement requirements, highlighting the importance of energy-resolved energetic-particle diagnostic for the mission of ITER. However, it has been found in recent years that the velocity-space interrogation regions of the foreseen energetic-particle diagnostics do not allow these measurements directly. We will demonstrate this for gamma-ray spectroscopy, collective Thomson scattering, neutron emission spectroscopy and fast-ion D-alpha spectroscopy by invoking just energy and momentum conservation. The consequences of these conservation laws highlight analogies and differences between the velocity-space sensitivities of the diagnostics. Nevertheless, alpha-particle energy spectra and densities can be inferred at ITER for energies larger than 1.7 MeV through integrated data analysis of CTS and GRS by velocity-space tomography. Further, assuming isotropy their energy spectra can also be inferred by 1D inversion of spectral single-detector measurements, allowing the recovery of alpha-particle energy spectra and densities down to about 300 keV by CTS. Examples of these inversion formalisms will be given.

Primary author

Dr Mirko Salewski (Technical University of Denmark)

Co-authors

Dr Asger Schou Jacobsen (Max-Planck-Institut fuer Plasmaphysik, Garching, Germany) Dr Benedikt Geiger (IPP Garching) Ms Birgitte Madsen (Technical University of Denmark) Dr Dmitry Moseev (IPP Greifswald) Dr Eriksson Jacob (Uppsala University) Dr Frank Leipold (Technical University of Denmark) Prof. Giuseppe Gorini (Universita' degli Studi di Milano-Bicocca) Ms Ivana Abramovic (Max-Planck-Institut f\"ur Plasmaphysik, Greifswald, Germany) Dr Jesper Rasmussen (Technical University of Denmark) Dr Marco Tardocchi (MIB) Dr Massimo Nocente (Dipartimento di Fisica - Università di Milano-Bicocca) Dr Stefan Nielsen (Technical University of Denmark) Dr Søren Bang Korsholm (Risø DTU National Laboratory for Sustainable Energy) Dr Vasily Kiptily (UKAEA Fusion)

Presentation Materials