Core toroidal rotation in impurity seeded H2 & D2 plasma of ADITYA-U tokamak*

Intrinsic toroidal rotation has been observed in the core region of ADITYA-U tokamak without applying any external torque, using Doppler shift spectroscopy. A multi-track visible spectrometer is utilized to obtain the spectral lines of the main impurity ions (C⁵⁺ ions) at 529.05nm to measure the Doppler shift. Core toroidal rotation is observed to reverse its direction above a certain density in ADITYA-U plasma [1]. However the edge toroidal rotation is observed to reverse its direction above a certain threshold of plasma current [2]. To understand a better picture of intrinsic toroidal rotation in ADITYA-U tokamak, core and edge toroidal rotation is measured simultaneously in both Hydrogen and Deuterium plasma (separately) at a fixed B_T. The effect of impurity seeding is also studied on the core & edge rotation in both Hydrogen as well as Deuterium plasma to understand the underlying Physics behind the intrinsic toroidal rotation in different isotopic plasma (with and without impurity seeding).

 

References:

 

[1]  G. Shukla et al., Nucl. Fusion 59, 106049 (2019)

[2] Ankit Kumar et al Nucl. Fusion 64 086019 (2024)