[Table of Contents]

Plasma and Fusion Research

Volume 2, S1120 (2007)

Regular Articles

Tomographic Reconstruction of Emissivity Profile from Tangentially Viewed Images using Pixel Method
Santanu BANERJEE, Asim Kumar CHATTOPADHYAY and P. VASU
Institute for Plasma Research, Bhat, Gandhinagar 382 428, Gujarat, India
(Received 18 December 2006 / Accepted 17 June 2007 / Published 20 November 2007)

Abstract

Fast camera systems for imaging tokamak plasmas are becoming increasingly popular. Edge fluctuations and plasma instabilities can be imaged in the visible and X-ray wavelengths using presently available cameras. While viewing the plasma tangentially, the lines of sight (LOS) pass through the plasma integrating the light through a number of flux surfaces. Here we report a reconstruction code for tomographic unfolding of the emissivity profile of the poloidal cross section from the tangential image, using pixel method. The poloidal cross section of the tokamak has been divided into pixels, each of which is a footprint of a subtorus. The emissivity of each of this subtorus (pixels) is assumed to be constant and uniform around the torus.

Keywords

ray-torus intersection, tomographic reconstruction, pixel method

DOI: 10.1585/pfr.2.S1120

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This paper may be cited as follows:

Santanu BANERJEE, Asim Kumar CHATTOPADHYAY and P. VASU, Plasma Fusion Res. 2, S1120 (2007).