Simultaneous ELM suppression and divertor detachment via synergistic boron powder and neon injection in EAST

Journal Article · Mon Mar 16 00:00:00 UTC 2026 · Nuclear Fusion

DOI: https://doi.org/10.1088/1741-4326/ae4f00 · OSTI ID:3023477

Sun, Zhen  ^[1]; Maingi, Rajesh  ^[1]; Xu, Wei  ^[2]; Peng, Lei ^[3]; Li, Kedong  ^[2]; Lin, Xin  ^[2]; Cheng, Yunxin  ^[2]; Wu, Donggui  ^[2]; Ding, Fang  ^[2]; Wang, Zhe  ^[2]; Guan, Yanhong ^[2]; Wang, Minrui ^[2]; Chao, Yan ^[2]; Yang, Qingquan  ^[2]; Gan, Kaifu  ^[4]; Tao, Yuqiang  ^[5]; Bortolon, Alessandro  ^[1]; Wang, Huiqian  ^[6]; Zhou, Tianfu ^[2]; Huang, Jia ^[2] ; Wang, Wei  ^[2]; Jin, Yifei  ^[2]; Duan, Yanmin ^[2]; Xu, Yanzhen ^[2]; Diallo, Ahmed  ^[1]; Tritz, Kevin ^[7]; Nagy, Alexander  ^[1]; Schamis, Hanna  ^[1]; Zuo, Guizhong  ^[2]; Qian, Jinping  ^[2]; Gong, Xianzu  ^[2]; Hu, Jiansheng ^[2]

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1. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
2. Chinese Academy of Sciences (CAS), Hefei (China). Institute of Plasma Physics (IPP)
3. Henan University of Science and Technology, Zhengzhou (China)
4. Univ. of Tennessee, Knoxville, TN (United States)
5. Anhui Normal Univ., Wuhu (China)
6. General Atomics, San Diego, CA (United States)
7. Johns Hopkins Univ., Baltimore, MD (United States)

A novel approach for simultaneous power exhaust and edge-localized mode (ELM) control is presented in the Experimental Advanced Superconducting Tokamak discharges, which utilize an ITER-like tungsten divertor. Real-time injection of boron (B) powder and neon (Ne) gas overcomes their limitations encountered when used separately. Pure Ne seeding leads to a narrow operational window constrained by core impurity accumulation and H-mode to L-mode back transitions, while pure solid B injection (SBI) is insufficient for effective divertor cooling. In comparison, their combined use achieves a stable, stationary, ELM-suppressed H-mode with adequate power exhaust. This synergistic scenario features partial energy detachment at the outer divertor while maintaining good plasma confinement (H₉₈ ∼ 1) with minimal degradation. Two key features of this scenario are: (1) the SBI triggers a persistent Edge Harmonic Mode (EHM), which provides a crucial continuous particle transport channel, preventing Ne and tungsten/molybdenum accumulation without flushing out by ELM, and (2) the B + Ne mixture allows for active optimization of the radiated power profile. Core radiation can be reduced by substituting a portion of the Ne with B, leveraging their complementary non-coronal equilibrium radiation efficiencies. This combined B + Ne injection scheme presents a promising pathway toward integrated core-edge scenarios, offering the potential to minimize total impurity throughput while leveraging an actuator (powder injection) already being considered for ITER.

• Research Organization: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC02-09CH11466
• OSTI ID: 3023477
• Journal Information: Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 4 Vol. 66; ISSN 0029-5515; ISSN 1741-4326
• Publisher: IOP Science - IAEACopyright Statement
• Country of Publication: United States
• Language: English