Feasibility of the EDICAM camera for runaway electron detection in JT-60SA disruptions

TL;DR

This study assesses the EDICAM camera's capability to detect runaway electrons in JT-60SA disruptions by simulating synchrotron radiation and analyzing its observability, demonstrating potential for runaway electron characterization.

Contribution

The paper demonstrates, through simulation, that the EDICAM camera can effectively detect synchrotron radiation from runaway electrons in JT-60SA disruptions, showing its feasibility for runaway electron diagnostics.

Findings

Runaway electron beams produce observable synchrotron radiation.

EDICAM can potentially be used for runaway electron detection.

Simulation confirms feasibility of EDICAM for this purpose.

Abstract

The visible camera system EDICAM (Event Detection Intelligent Camera), recently installed on JT-60SA, is simulated to assess whether it can be used for measuring synchrotron radiation from relativistic runaway electrons. In this simulation, the SOFT synthetic synchrotron diagnostic framework is used to compute the synthetic synchrotron camera images from a JT-60SA-like disruption modelled with the DREAM disruption simulation code. In the studied scenario, a large amount of argon is added to the plasma, and a disruption is simulated by starting a prescribed exponential temperature drop and finishing with further cooling provided by the argon in a self-consistent simulation of the current quench. The background plasma evolution is calculated by DREAM self-consistently with the fast electron population, which is modelled kinetically. The resulting runaway electron distribution function along with the parameters of the EDICAM visible camera system are used as an input to the SOFT framework to assess the feasibility of the camera for runaway electron detection. We find that the runaway electron beam formed in the disruption can produce synchrotron radiation observable by the EDICAM system, thus enabling the use of the EDICAM for the characterization of runaway electron beams.