| Title: |
The effect of impurity seeding on edge toroidal rotation in the ADITYA-U tokamak |
| Authors: |
Ankit Kumar; K. Shah; M.B. Chowdhuri; N. Ramaiya; Aman Gauttam; K.A. Jadeja; Bharat Hedge; N. Yadava; Kaushlender Singh; Suman Dolui; Tanmay Macwan; Ashok Kumawat; Pramila Gautam; Laxmikanta Pradhan; Harshita Raj; G. Shukla; Dipexa Modi; S. Patel; Soumitra Banerjee; Injamul Hoque; Komal; Suman Aich; Ankit Patel; Utsav; A. Kanik; Rohit Kumar; Priyanka Verma; K.M. Patel; Kalpesh Galodiya; M. Shah; R.L. Tanna; Joydeep Ghosh |
| Source: |
Nuclear Fusion, Vol 64, Iss 8, p 086019 (2024) |
| Publisher Information: |
IOP Publishing |
| Publication Year: |
2024 |
| Collection: |
Directory of Open Access Journals: DOAJ Articles |
| Subject Terms: |
toroidal rotation; rotation reversal; impurity seeding; Nuclear and particle physics. Atomic energy. Radioactivity; QC770-798 |
| Description: |
Intrinsic toroidal rotation velocity ( V _φ ) has been measured from the Doppler shift of C ^5+ carbon spectral lines (at 529.05 nm) in the edge region of the ADITYA-U tokamak without any auxiliary torque input in an ohmically heated pure hydrogen (H _2 ) plasma as well as in H _2 plasmas seeded with medium-Z (neon and argon) impurities . The toroidal rotation in the edge region is observed to reverse its direction from the counter-current to the co-current direction with an increase in plasma current beyond I _p ∼ 145–150 kA. Furthermore, a systematic decrease in the co-current V _φ has been observed with the edge density, which tends to decrease to almost zero velocity with an increase in the edge density. The injection of medium- Z (neon and argon) impurities is observed to influence the edge toroidal rotation significantly. In low I _p discharges, argon injection leads to a reversal of edge intrinsic rotation from the counter-current to the co-current direction. In high I _p discharges, both neon and argon seeding enhance the co-current rotation by about ∼5–10 km s ^−1 , at a constant I _p compared to pure H _2 discharges. Simultaneous measurements of the edge radial electric field, E _r , shows that the E _r × B _θ flow seems to be driving the edge toroidal rotation in ADITYA-U. With impurity injection, the E _r also gets modified, leading to an observed increase in the edge toroidal rotation. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| Relation: |
https://doi.org/10.1088/1741-4326/ad4c5a; https://doaj.org/toc/0029-5515; https://doaj.org/article/5419475b78e04192831702995787b0f1 |
| DOI: |
10.1088/1741-4326/ad4c5a |
| Availability: |
https://doi.org/10.1088/1741-4326/ad4c5a; https://doaj.org/article/5419475b78e04192831702995787b0f1 |
| Accession Number: |
edsbas.92DB5CB |
| Database: |
BASE |