201. Observation of poloidal asymmetry in measured neutral temperatures in the Aditya-U tokamak plasma
- Author
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Ritu Dey, Rakesh L. Tanna, K. A. Jadeja, Nandini Yadava, Deepti Tripathi, Malay Bikas Chowdhuri, Rohit Kumar, K.M. Patel, Sripathi Punchithaya K, Jiten Ghosh, Santanu Banerjee, Harshita Raj, and R. K. Manchanda
- Subjects
Physics ,Nuclear and High Energy Physics ,Zeeman effect ,Tokamak ,Balmer series ,Plasma ,Condensed Matter Physics ,01 natural sciences ,Spectral line ,010305 fluids & plasmas ,law.invention ,symbols.namesake ,law ,0103 physical sciences ,symbols ,Emission spectrum ,Atomic physics ,010306 general physics ,Neutral particle ,Doppler broadening - Abstract
The neutral particle temperature in the edge region of the Aditya-U tokamak has been measured by recording the hydrogen Balmer alpha emission spectra at 656.28 nm from different lines of sight in both the high and low field sides. The spatial profile of the H α emission has been recorded using a 1 m multi-track spectrometer. The neutral temperature is estimated from the Doppler broadening of the measured H α spectrum by appropriately removing the contribution from the Zeeman splitting of the spectral lines. A computer simulation code was developed to estimate the neutral temperature by including the broadening mechanisms such as Doppler broadening and the Zeeman effect to simulate the H α emission spectrum along with the proper convolution of the instrumental width of the diagnostic system. It has been observed that the high field side neutral temperature (~4–6 eV) during plasma flat top is almost twice that of the low field side (~2–3 eV) suggesting poloidal asymmetry in the neutral temperature.
- Published
- 2019