X. Y. Song
A5102742117- Magnetic confinement fusion research
- Laser-Plasma Interactions and Diagnostics
- Ionosphere and magnetosphere dynamics
- Fusion materials and technologies
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Quantum Chromodynamics and Particle Interactions
- Digital Games and Media
- Artificial Intelligence in Games
- Social Media and Politics
- Augmented Reality Applications
- Sleep and related disorders
- Museums and Cultural Heritage
- Black Holes and Theoretical Physics
- Hong Kong and Taiwan Politics
- Internet Traffic Analysis and Secure E-voting
- Education and Learning Interventions
- Superconducting Materials and Applications
- Nuclear reactor physics and engineering
- Metal and Thin Film Mechanics
- Nuclear Physics and Applications
- Particle physics theoretical and experimental studies
- Art, Technology, and Culture
- Semiconductor materials and devices
- Virtual Reality Applications and Impacts
Aalto University
2023-2025
Southwestern Institute of Physics
2011-2023
Chaohu Hospital of Anhui Medical University
2021
The features of ion and electron fishbone instabilities have been investigated during neutral beam injection (NBI) cyclotron resonance heating (ECRH) on HL-2A. Some new phenomena, such as frequency jumps V-font-style sweeping, presented in the paper. Three kinds i-fishbones, including hybrid sawtooth–fishbone (sawbone), run-on classical fishbone, identified NBI. During high power ( P ECRH > 0.7 MW) ECRH, experimental results indicate that e-fishbone frequencies are higher than those low...
The wide adoption of Large Language Models (LLMs) has attracted significant attention from \textit{jailbreak} attacks, where adversarial prompts crafted through optimization or manual design exploit LLMs to generate malicious content. However, optimization-based attacks have limited efficiency and transferability, while designs are either easily detectable demand intricate interactions with LLMs. In this paper, we first point out a novel perspective for jailbreak attacks: more responsive...
Two experiment campaigns were conducted on the HL-2A tokamak in 2003 and 2004 after first plasma was obtained at end of 2002. Progresses many aspects have been made, especially divertor discharge feedback control configuration. Up to now, following operation parameters achieved: Ip = 320 kA, Bt 2.2 T duration Td 1580 ms. With current horizontal position, an excellent repeatability has achieved. The operated both limiter configuration single null (SN) SN is simulated with MHD equilibrium code...
Recent experiment results from the HL-2A tokamak are presented in this paper. Supersonic molecular beam injection (SMBI) with liquid nitrogen temperature propellant is used. Low SMBI can form hydrogen clusters that penetrate into plasma more deeply and efficiently. Particle diffusion coefficient convection velocity (D = 0.5–1.5 m2 s−1 Vconv < 40 m s−1, respectively) obtained at periphery using modulated SMBI. Multi-probe measurements reveal 0–1, n 0 symmetries of directly measured low...
Significant experimental advances have been made on the HL-2A tokamak along with substantial improvement and development of hardware. A spontaneous particle transport barrier has observed in Ohmic discharges without any external momentum input. The was evidenced by a density perturbation study using modulated supersonic molecular beam injection (SMBI) microwave reflectometry. new features non-local effect induced SMBI analysed. three-dimensional spectral structures low frequency zonal flow,...
A strong burst of the internal kink mode has been observed during ECRH on HL-2A. It experimentally identified that energetic electrons, which deviate from Maxwell velocity distribution, excite mode, was a so-called electron fishbone (e-fishbone). The energy distribution electrons is indirectly measured by hard x-ray detector (CdTe) with pulse height analysis. When counts 35–70 keV increase to higher level, can be obviously observed. e-fishbone excited off-axis deposited both high field side...
The physics experiments on the HL-2A tokamak have been focused confinement improvement, particle and thermal transport, zonal flow turbulence, filament characteristics, energetic induced modes plasma fuelling efficiency since 2008. ELMy H-mode discharges are achieved in a lower density regime using combination of NBI heating with ECRH. power threshold is found to increase decrease density, almost independent launching order ECRH power. pedestal profiles measured. outward convection observed...
A new scintillator-based lost fast-ion probe (SLIP) has been developed and operated in the HL-2A tokamak [L. W. Yan, X. R. Duan, T. Ding, J. Q. Dong, Yang, Yi Liu, L. Zou, D. M. Xuan, Y. Chen, Rao, Song, Huang, C. Mao, Wang, Li, Z. Cao, B. G. Lei, H. Zhang, Cui, Deng, Feng, Gao, Han, Hong, Ji, Kang, F. Kong, Lan, S. Qing A. Luo, Pan, Peng, Shi, Sun, K. Xiao, Xie, Yao, Yu, Yuan, Zhao, Zhong, Zhou, Team, Nucl. Fusion 51, 094016 (2011)] to measure losses of neutral beam ions. The design is...
Abstract The evolutions of MHD instability behaviors and enhancement both electrostatic electromagnetic turbulence towards the plasma disruption have been clearly observed in HL-2A plasmas. Two types disruptive discharges investigated for similar equilibrium parameters: one with a distinct stage small central temperature collapse ( $$\sim$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>∼</mml:mo> </mml:math> 5–10%) around 1 millisecond before thermal quench (TQ), while...
In this paper, an overview of the magnetohydrodynamic instabilities induced by energetic electrons on HL-2A is given and some new phenomena with high-power electron cyclotron resonance heating (ECRH) are presented. A toroidal Alfvén eigenmode frequency from 200 to 350 kHz identified during powerful ECRH. lower range 10 35 kHz, which in beta-induced range, coexistence multi-mode found ECRH for first time. The spectra become wide when power sufficiently high. frequencies modes increase much...
Characteristics of fast-ion losses induced by various magnetohydrodynamic (MHD) instabilities, such as tearing mode (TM), long-lived (LLM), and sawtooth crash, have been observed experimentally investigated in the HL-2A tokamak. To study losses, a new scintillator-based lost-fast ion probe has developed used, an increment loss rate MHD amplitude increase measured. Compared with TM LLM, crash broad range energy pitch angle. There may be some interactions between fast ions magnetic...
In an experimental study of the runaway electron generation during major disruptions in HuanLiuqi-2A (commonly referred to as HL-2A) [L. W. Yan, Nucl. Fusion 51, 094016 (2011)] tokamak, detailed time and space resolved x-ray images long-lived beam flight have been observed these allow a analysis evolution disruption produced disruption, where conversion efficiency pre-disruption plasma current into is up 55% on HL-2A tokamak. Moreover, delay about 7 ms between start formation has found. With...
Physics related to fast ions in magnetically confined fusion plasmas is a very important issue, since these particles will play an role future burning plasmas. Indeed, they act as primary heating source and sustain the self-ignited condition. To measure ion slowing-down times magnetohydrodynamic-quiescent different scenarios, short pulses of deuterium neutral beam, so-called “blip,” with duration about 5 ms were tangentially co-injected into at HuanLiuqi-2A (commonly referred HL-2A) tokamak...
Physics related to fast electrons in lower hybrid (LH) current drive (LHCD) plasma is a very important issue, since these particles will play an role runaway electron (RE) generation and wave (LHW)-related physics. Utilizing new hard X-ray (HXR) pinhole camera, recent HL-2A tokamak experiments have devoted enhancing the understanding of physics on LHW. The bremsstrahlung (FEB) emission HXR energy range between 20 200 keV was measured by camera. To study conversion LHW-produced into REs,...
A new radial neutron camera system has been developed and operated recently in the HL-2A tokamak to measure spatial time resolved 2.5 MeV D-D fusion neutron, enhancing understanding of energetic-ion physics. The mainly consists a multichannel collimator, liquid-scintillation detectors, shielding systems, data acquisition system. Measurements neutrons using have successfully performed during 2015 experiment campaign. measurements show that distribution plasma peaked profile, suggesting...
A hard X-ray pinhole camera system has been recently built at the HL-2A tokamak to measure evolution of space-time distribution fast electrons in energy range 20 200 keV. The is mainly composed a fan-shaped detector array, an observation window, mechanism, and data processing system. array consists 21 CdTe detectors that are arranged poloidal section. views plasma perpendicularly through window mounted horizontal port on equatorial plane. implemented by spectrometry based field-programmable...
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Y. P. Zhang, Yi Liu, J. W. Yang, X. Song, G. L. Yuan, Zhou, H. Yao, B. Feng, Li, Q. R. Duan, C. Pan, HL-2A Team; Enhanced production of runaway electrons during electron cyclotron resonance heating in the presence supersonic molecular beam injection tokamak. Phys. Plasmas 1 July 2010; 17 (7): 072509....
Hong Kong’s controversy over the Anti-extradition Bill Movement triggered a large-scale social movement, which gradually evolved from relatively peaceful demonstrations to prolonged series of conflicts and even street violence. Kong students are most front-line participants. Social media important platforms for youth political mobilization organization. The growing polarization on has led problems such as unfriending cyberbullying. This study interviewed 96 investigate their practices media,...