SOFT: A synthetic synchrotron diagnostic for runaway electrons
Journal article, 2018

Improved understanding of the dynamics of runaway electrons can be obtained by measurement and interpretation of their synchrotron radiation emission. Models for synchrotron radiation emitted by relativistic electrons are well established, but the question of how various geometric effects -- such as magnetic field inhomogeneity and camera placement -- influence the synchrotron measurements and their interpretation remains open. In this paper we address this issue by simulating synchrotron images and spectra using the new synthetic synchrotron diagnostic tool SOFT (Synchrotron-detecting Orbit Following Toolkit). We identify the key parameters influencing the synchrotron radiation spot and present scans in those parameters. Using a runaway electron distribution function obtained by Fokker-Planck simulations for parameters from an Alcator C-Mod discharge, we demonstrate that the corresponding synchrotron image is well-reproduced by SOFT simulations, and we explain how it can be understood in terms of the parameter scans. Geometric effects are shown to significantly influence the synchrotron spectrum, and we show that inherent inconsistencies in a simple emission model (i.e. not modeling detection) can lead to incorrect interpretation of the images.


Mathias Hoppe

Chalmers, Physics, Subatomic and Plasma Physics

Ola Embréus

Chalmers, Physics, Subatomic and Plasma Physics

R A Tinguely

R Granetz

Adam Stahl

Chalmers, Physics, Subatomic and Plasma Physics

Tünde Fülöp

Chalmers, Physics, Subatomic and Plasma Physics

Nuclear Fusion

0029-5515 (ISSN)

Vol. 58 2 026032-

Driving Forces

Sustainable development

Areas of Advance



Basic sciences

Subject Categories

Fusion, Plasma and Space Physics



More information

Latest update