2019年11月6日星期三

Laser light pressure ion acceleration dynamic stabilization of a new program

The intense laser-matter interaction allows the charge-separation field to be as high as 100 GV / m, which is three orders of magnitude greater than conventional RF accelerators and accelerates charged particles to GeV energy within a centimeter range, thus replacing the traditional Accelerators have aroused widespread interest in the scientific community.

Among many laser ion acceleration mechanisms, ion beam obtained theoretically by Radiation Pressure Acceleration (RPA) has the characteristics of small energy dispersion, large beam density and high energy conversion efficiency. It is the frontier and hot point of current research. Although the RPA theory and one-dimensional simulation results are very attractive, it is still difficult to obtain the expected good results in the experiment at present. However, the most important reason for removing the experimental laser target parameters is the violent development of instability in high-dimensional conditions. The mainstream view is that mainly Rayleigh-Taylor (RT) instability has a negative impact. This instability eventually leads to electron heating and mass loss in the simultaneously accelerated plasma sheet, resulting in a Coulomb explosion of the plasma sheet, accelerated destruction, and ultimately poor ion beam quality.

How to curb the occurrence of instability is one of the most challenging issues in RPA research at present. Many methods have been proposed and studied, but the actual results have not been satisfactory.

Fig.1 Schematic diagram of dynamic stabilization of light pressure acceleration

After years of in-depth research, Qiao Bin task force at Peking University, another way, according to a completely different idea, consider how to dynamically compensate for the acceleration of light pressure instability instability caused by the role of Rather than just suppress the instability of this One idea is that the ionization effect of high-Z coating is proposed for the first time to dynamically replenish electrons during the acceleration of laser light to compensate for the electron loss of the accelerated plasma sheet caused by RT instability so as to achieve dynamic stabilization RPA (Figure 1) . This new approach is very "skinned" and three-dimensional particle simulations show that with the current real laser and target parameters, this scheme enables stable photoionization acceleration and can be used to accelerate high-Z heavy ion sources (Figure 2).

Figure 2 Three-dimensional particle simulation results. Considering ionization (a) and without ionization (b), at the end of laser action, the isosurface distribution of Al13 + ion density; (c) The energy spectrum of the corresponding Al13 + ion (red line represents ionization, blue line represents Consider the case of ionization).

Relevant research results recently published in Physical Review Letters [118, 204802 (2017)]. The PRL reviewer gave a high evaluation of the program and believed that this work made an important contribution to the research field of laser light acceleration and revealed the importance of dynamic ionization in the interaction between intense laser and heavy ions.

Qiao Bin task force PhD student Shen Xiaofei as the first author of the paper, researcher for the correspondent Qiao Bin, collaborators include Zhou Cangtao researcher, academician He Xian Tu.


The QUANTUM range of Pneumatic Conveying Systems and Equipment truly offers a complete end-to-end solution for those materials best conveyed via airflows.



Our aim is to utilise our range of pneumatic conveying systems to improve product flows and eliminate plant bottlenecks while economically and efficiently conveying material throughout your facility. Whether it is loading or unloading silos and bags, batching material into a process, or simply moving material from A to B, QUANTUM has the system to do the job.


At QUANTUM, we are acutely aware of geographical problems that face our clients around the world, such as high humidity and condensation. If not taken into account, these factors can render a pneumatic conveying system inoperable. Where necessary, QUANTUM incorporates de-humidification and air chilling to ensure a robust and trouble free system.



The QUANTUM range of Pneumatic Conveying equipment and systems includes:

• Air-slides

• Vacuum systems

• Dust collection systems

• Dense phase conveyors

• Dilute phase conveyors

• Fume extraction systems


Typical Pneumatic Conveying Applications include:

• Bag house dust

• Lime

• Calcium carbonate

• Limestone

• Carbon black

• PVC resin

• Activated carbon

• Soda ash

• Cement

• Sugar

• Fly-ash

• Talc


Pneumatic Conveyor

Pneumatic Conveyor,Dilute Phase Conveyor,Dense Phase Transporter,Dilute Phase Pneumatic Conveyor

Quantum Conveying Systems Yangzhou Co.,Ltd. , https://www.quantum-sino.com

没有评论:

发表评论