Signal Convolution in Spectroscopy and Its Implication for Diagnosing the Rotation of the TCABR Tokamak

• Grant number: 24/08709-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2024
• End date: August 31, 2025
• Field of knowledge: Physical Sciences and Mathematics - Physics - Physics of Fluids, Plasma Physics and Electrical Discharge
• Principal Investigator: José Helder Facundo Severo
• Grantee: Vinicius Murbach Toth
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 22/04857-2 - Development of an innovative set of ELM control coils for the TCABR tokamak, AP.JP

Abstract

Since the thematic project (FAPESP proc. 2022/05491-1) includes the modernization of plasma rotation diagnostics, this project aims to conduct a detailed study of the sensitivity of the new diagnostic system and the uncertainties in the rotation velocity measurements. The central focus is to enhance the understanding and accuracy of measuring the poloidal and toroidal rotation velocities of the plasma, which are essential for optimizing the performance of the fusion reactor. Using a new monochromator with a longer focal length and advanced multichannel detectors, the project seeks to mathematically correlate the ratio of output signals with the Doppler shift of spectral lines. This method allows for a more precise estimate of the uncertainties in velocity measurements, crucial for the analysis of momentum and energy transport in the plasma.By integrating 32 measurement channels, the upgraded system will facilitate the simultaneous acquisition of rotation profiles, significantly expanding the temporal and spatial analysis capabilities of plasma dynamics. This study will detail how variations in the monochromator parameters influence the diagnostic sensitivity, enabling the detection of minimal velocities with greater precision. Additionally, the theoretical model developed will be validated through comparisons with experimental data obtained during calibration processes, contributing to more effective methodologies in future controlled nuclear fusion research.