A brief review：experimental investigation of zonal flows and geodesic acoustic modes in fusion plasmas

Zonal flows self-generated by turbulence play an important role in regulating turbulence,reducing transport level,and thus improve plasma confinement in fusion plasmas.The zonal flows and geodesic acoustic modes have been identified in various devices.The related issues,such as the poloidal and toroidal symmetries,coupling to turbulence,effects on turbulence and transport,nonlinear energy transfer between turbulence and zonal flows,dependence of the plasma parameters,roles in the confinement regime transitions etc are overviewed briefly in this paper.The interaction between zonal flows and magnetic islands is emphasized.

Kinetic Alfvén waves in a deuterium-tritium fusion plasma with slowing-down distributed α-particles

The dispersion relation and damping rate of kinetic Alfvén waves(KAWs) in a deuterium-tritium fusion plasma with slowing-down distributed α-particles are investigated using the kinetic theory. The variations of wave frequency and damping rate with respect to the α concentration(n_(α)/n_(e)) and perpendicular wave number(k_(⊥)) are studied from a numerical way. The results show that the fluctuation of α concentration slightly affects the frequency and damping rate of KAWs at low n_(α)/n_(e). In addition, the frequency and the damping rate increase as the k_(⊥) and the background temperature Te increase. For comparison, the calculations are performed also in the case of α-particles following an equivalent Maxwellian distribution. For a given k_(⊥), the value of the frequency obtained in the slowing-down distribution case is smaller than that obtained in the Maxwellian distribution case. Conversely, the value of the damping rate obtained in the slowing-down distribution case is slightly larger than that obtained in the Maxwellian distribution case.

Quantum Transport Theory for Fusion Plasmas

Fundamental quantum transport equation for impact-ionization processes in fusion plasmas is formulated in the actor-spectator description. The density-matrix formulism is adopted to treat both coherent and incoherent effects in a unified fashion. Quantum electrodynamic effects are also considered for high-temperature scenarios. Electron-impact ionization of uranium ion U91＋ and proton-impact ionization of hydrogen are given as examples.

Implosion Plasma Driven Fusion Pellet of Inertial Confinement(A Short Memorandum)

The implosion plasma drive fusion pellet of inertial confinement is a concept related to nuclear fusion,a process in which atomic nuclei combine to form heavier nuclei,releasing a large amount of energy in the process.The implosion plasma drive fusion pellet is a potential fuel source for achieving controlled nuclear fusion.ICF(inertial confinement fusion)is a technique used to achieve fusion by compressing a small target containing fusion fuel to extremely high densities and temperatures using lasers or other methods.The implosion plasma drive fusion pellet concept involves using a small pellet of deuterium and tritium(two isotopes of hydrogen)as fusion fuel,and then rapidly heating and compressing it using a pulsed power system.The implosion process creates a high-pressure plasma that ignites the fusion reactions,releasing energy in the form of neutrons and charged particles.The resulting energy can be captured and used for power generation.This technology is still in the experimental stage,and significant research and development is required to make it commercially viable.However,it has the potential to provide a virtually limitless source of clean energy with no greenhouse gas emissions or long-term radioactive waste.Be that as it may,ICF has to get exact control of the implosion process,mitigate insecurities,and create modern materials and advances to resist the extraordinary conditions of the combined response.

Positions Open in the Field of Plasma and Fusion

Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is searching for 5 senior and 10 junior scientists of plasma and fusion in the following superconducting tokamak research areas: theory and simulation, diverter and edge physics, plasma diagnostics, electron cyclotron resonant heating, ion cyclotron resonant heating, lower hybrid wave, neutral beam injection, reactor design, fusion material, superconducting engineering.

Positions Open in the Field of Plasma and Fusion

Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is searching for 5 senior and 10 junior scientists of plasma and fusion in the following superconducting tokamak research areas: theory and simulation, diverter and edge physics, plasma diagnostics, electron cyclotron resonant heating, ion cyclotron resonant heating, lower hybrid wave, neutral beam injection, reactor design, fusion material, superconducting engineering.

Positions Open in the Field of Plasma and Fusion

Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important Laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is searching for 5 senior and 10 junior scientists of plasma and fusion in the following superconducting tokamak research areas: theory and simulation, diverter and edge physics, plasma diagnostics, electron cyclotron resonant heating, ion cyclotron resonant heating, lower hybrid wave, neutral beam injection, reactor design, fusion material, superconducting engineering.

Nuclear Fusion Within Extremely Dense Plasma Enhanced by Quantum Particle Waves

Quantum effects play an enhancement role in p-p chain reactions occurring within stars. Such an enhancement is quantified by a wave penetration factor that is proportional to the density of the participating fuel particles. This leads to an innovative theory for dense plasma, and its result shows good agreement with independent data derived from the solar energy output. An analysis of the first Z-pinch machine in mankind＇s history exhibiting neutron emission leads to a derived deuterium plasma beam density greater than that of water, with plasma velocities exceeding 10000 km/s. Fusion power could be achieved by the intersection of four such pinched plasma beams with powerful head-on collisions in their common focal region due to the beam and target enhanced reaction.

Cold Fusion Based on Matter-Antimatter Plasma Formed in Molecular Crystals

The main purpose of this work is to shed light on the possibility of producing huge amount of energy based on the construction matter-antimatter plasma in a molecular crystal. It is assumed that two beams of isothermal hydrogen and antihydrogen are injected into a palladium crystal leading to a plasma state composed of particles and antiparticles. The collapse of this state releases a huge amount of energy which can be used as fuel for space shuttles. Thus, the novel system of isothermal pressure interaction enhances the energy power carried out by the quantum ion acoustic soliton (QIAS). In addition to the energy power released from the particle-antiparticle annihilation. The probability of merging the energy from these two cases is available at certain condition. The released energy may be a significant step in solving the energy scape of Tokomak to produce fusion energy. The study starting from the one-dimensional quantum hydrodynamic model (in which the term of electron-positron and proton-antiproton for hydrogen-antihydrogen is included), a Korteweg de Vries equation (kdv) is derived, the QIAS energy experiences and the annihilation energy power are calculated. It is found that the total energy of QIAS and the energy resulting from hydrogen-antihydrogen annihilation are important step towards the establishment of a cold fusion power station.

Induction System for a Fusion Reactor: Quantum Mechanics Chained up

In the quest for a sustainable and abundant energy source, nuclear fusion technology stands as a beacon of hope. This study introduces a groundbreaking quantum mechanically effective induction system designed for magnetic plasma confinement within fusion reactors. The pursuit of clean energy, essential to combat climate change, hinges on the ability to harness nuclear fusion efficiently. Traditional approaches have faced challenges in plasma stability and energy efficiency. The novel induction system presented here not only addresses these issues but also transforms fusion reactors into integrated construction systems. This innovation promises compact fusion reactors, marking a significant step toward a clean and limitless energy future, free from the constraints of traditional power sources. This revolutionary quantum induction system redefines plasma confinement in fusion reactors, unlocking clean, compact, and efficient energy production.

Detection of fusion gene in cell-free DNA of a gastric synovial sarcoma

Synovial sarcoma(SS) is genetically characterized by chromosomal translocation, which generates SYT-SSX fusion transcripts. Although SS can occur in any body part, primary gastric SS is substantially rare. Here we describe a detection of the fusion gene sequence of gastric SS in plasma cell-free DNA(cf DNA). A gastric submucosal tumor was detected in the stomach of a 27-year-old woman and diagnosed as SS. Candidate intronic primers were designed to detect the intronic fusion breakpoint and this fusion sequence was confirmed in intron 10 of SYT and intron 5 of SSX2 by genomic polymerase chain reaction(PCR) and direct sequencing. A locked nucleic acid(LNA) probe specificto the fusion sequence was designed for detecting the fusion sequence in plasma and the fusion sequence was detected in preoperative plasma cfD NA, while not detected in postoperative plasma cfD NA. This technique will be useful for monitoring translocation-derived diseases such as SS.

A Molecular Dynamics Study on the Dust-Plasma/Wall Interactions in the EAST Tokamak

The interactions between the W nano-dust and deuterium plasma at different lo- cations of the EAST tokamak are simulated using a molecular dynamics code. It is shown that nano-dust particles, with the radius, Rd, ~5 nm, can exist for at least several nano-seconds under the interactions from the ions without being ablated in some specific places of the tokamak edge plasma, while those with Rd ≥~25 nm may be ablated if the plasma temperature T~ 50 eV and density n^10^19 m-3. In addition, the collisions of tungsten nano-dust grains with a tungsten wall at 100 m/s or I000 m/s impinging speeds are simulated. It is demonstrated that the dust will stick to the wall, and the collision will not cause substantial damage to the wall, but it may be able to cause partial destruction of the dust grains themselves depending on their incident speeds.

The Plasma Channel Evolution Characteristics of Pulsed Flashlamps Working in an Array

This work is devoted to the study of plasma channel evolution characteristics in pulsed xenon flashlamps working in an array. Influencing factors on the plasma channel evolution process are studied, including pre-ionization pulse and neighbor fiashlamps. It has been found that neighbor flaShlamps affect the plasma channel by shaping the electric potential distribution, rather than by Lorentz force. Branching is observed in the plasma channels of the flashlamps in the middle of the array. Inconsistency also exists in the plasma channels of these flashlamps in different tests. The branching and inconsistency are both caused by the unique electric field distribution in these flashlamps. Besides, the pre-ionization pulse can help the main pulse plasma channel to develop more smoothly and faster, which will weaken the shock wave and benefit the mechanical strength of the flashlamp.

Estimation of plasma equilibrium parameters via a neural network approach

Plasma equilibrium parameters such as position, X-point, internal inductance, and poloidal beta are essential information for efficient and safe operation of tokamak. In this work, the artificial neural network is used to establish a non-linear relationship between the measured diagnostic signals and selected equilibrium parameters. The estimation process is split into a preliminary classification of the kind of equilibrium(limiter or divertor) and subsequent inference of the equilibrium parameters. The training and testing datasets are generated by the tokamak simulation code(TSC), which has been benchmarked with the EAST experimental data. The noise immunity of the inference model is tested. Adding noise to model inputs during training process is proved to have a certain ability for maintaining performance.

Diagnosis of the surface morphology of laser-ablated materials using the weightedDCT approach in laser speckle interferometry for application to plasma facing materials

To implement on-line, real-time monitoring for the surface morphology of Plasma-Facing Materials(PFMs) in tokamak, we developed a Laser Speckle Interferometry measurement approach. A laser ablation method was used to simulate the erosion process during Plasma-Wall Interactions in a tokamak. In the present investigation, we evaluated the results of laser ablation morphology changes on the surface of Mo material reconstructed by four different approaches(Flood-fill, Quality-guided, Discrete Cosine Transform(DCT) and Weighted-DCT). The morphology results measured by the weighted-DCT approach are very close to the measurement results from confocal microscopy with an average error rate within 7%. It is verified that the weighted-DCT algorithm has high accuracy and can efficiently reduce the influence of noise pollution coming from laser ablation, which is used as a proxy for erosion from plasma wall interaction. Additionally, the CPU computer time has been shortened. This is of great significance for the real-time monitoring of PFMs’ morphology in the Experimental Advanced Superconducting Tokamak(EAST) in the future.

Effect of tritium reduction in determining energy gain by using R-matrix method direct laser fusion in D-T reaction

The laser fusion criterion is known as the ρR-Criterion, also called high-gain condition. This parameter is temperature dependent and can be calculated by R-matrix method. This method is applied for determining improved fusion cross-section for the reactions T(d,n)4He, 3He(d,p)4He, D(d,p)T, D(d,n)3He. In this paper the time dependent reaction rate equations for fusion reaction T(d,n)4He are solved and by using the obtained results we computed the fu- sion power density, energy gain versus temperature and ρR-parameter. The obtained results show that a suitable com- bination may be a deuterium fraction fD=0.65 and fT=0.35 which would lead 30% reduction in the tritium content of the fuel mixture, and this choice would not change the energy gain value very much. Finally, the obtained energy gain for D-T reaction by using R-matrix is in good agreement with other theories.

Ignition Conditions for Simulated Fuel Pellets in Degenerate Plasma

A high-density, low-temperature plasma can be obtained during the compression phase in inertial confinement fusion. When high density and low temperature are reached in the plasma in the fast ignition approach, the plasma electrons can be degenerate. The electronic stopping of a slow ion is smaller than that given by the classical formula, because some transitions between the electron states are forbidden. In this case, bremsstrahlung emission is strongly sup- pressed and the ignition temperature becomes lower than that in classical plasma. The equations that predict the behavior of these plasmas are different from the classical ones, and this is the main factor in the process of decreasing the ignition temperature of the plasma. In this work, physical conditions of ignition are studied by calculating the effect of radiation loss on the ignition temperature for a simulated fuel pellet, （D/Tx/3Hey）, in degenerate plasma. In fast ignition, the energy needed for obtaining high densities is minimized and the gain can be increased considerably.

Tandem Mirror Experiment for Basic Fusion Science

Research on controlled nuclear fusion has been largely concentrated on plasma confinement using toroidal magnetic fields. Toroidal systems are complex. A simpler magnetic confinement system may provide a valuable platform for understanding fusion plasmas. The linear mirror machine has delivered good performance with the potential of giving a direct conversion of nuclear energy into electric power. The GAMMA-10 (G-10) linear mirror confinement system at Tsukuba University demonstrated the principle of the direct conversion of plasma energy into electric power on a small scale from the exhaust plasma in the exterior divertor chamber. The tokamak fusion system has to prove that the 10 to 15 MA of plasma current can be sustained continuously with acceptable efficiency. Plasma confinement is due to the magnetic field from the plasma current in tokamaks. There is room for creative new solutions in the magnetic confinement of fusion plasmas, and consideration is given for the alternative approach of using a linear machine with high magnetic mirror fields and the direct conversion of the high temperature escaping plasma to electric power.

Vortex Method of Localization of Thermonuclear Plasma

An important task of world energy is to solve the problem of controlled thermonuclear fusion and the information presented in the article can be used in power engineering to create a controlled thermonuclear reactor. The method now used magnetic localization of plasma does not allow sustaining stable thermonuclear plasma in a closed chamber, and so another solution to the problem is necessary. In this paper, we propose an alternative dynamic approach of the stationary localization of plasma through centrifugal force. Localization of plasma as plasma whirlwind allows us to control the process of stable thermonuclear fusion.

Fusion Material Studies Relating to Safety in Russia in 2002

The paper is a summary of Russian material studies performed in frames of activi-ties aiming at substantiation of safety of the International Thermonuclear Experimental Reactor(ITER)after 2001.Subthreshold sputtering of tungsten by 5 eV deuterons was revealed at temper-atures above 1150℃.Mechanism of globular films formation was further studied.Computations of tritium permeation into vacuum vessel coolant confirmed the acceptability of vacuum vessel cooling system for removal of the decay heat.The most dangerous accident with high-current are in toroidal superconducting magnets able to burn out a bore up to 0.6 m in diameter in the cryostat vessel was determined.Radiochemical reprocessing of V-Cr-Ti alloy and its purification from activation products down to a contact dose rate of~10μSv/h was developed.