The propagation characteristics of the beam under various initial conditions are in-vestigated by means of PIC method.The influences of density modulation and velocity modulationon the propagation characteristics are ...The propagation characteristics of the beam under various initial conditions are in-vestigated by means of PIC method.The influences of density modulation and velocity modulationon the propagation characteristics are discussed and compared.The results reveal that by chang-iug the amplitude of the two kinds of modulations and the phase difference between them,the展开更多
We present a new mechanism of energy gain of electrons accelerated by a laser pulse. It is shown that when the intensity of an Tiltrafast intense laser pulse decreases rapidly along the direction of propagation, elect...We present a new mechanism of energy gain of electrons accelerated by a laser pulse. It is shown that when the intensity of an Tiltrafast intense laser pulse decreases rapidly along the direction of propagation, electrons leaving the pulse experience an action of ponderomotive deceleration at the descending part of a lower-intensity laser field than acceleration at the ascending part of a high-intensity field, thus gain net energy from the pulse and move directly forward. By means of such a mechanism, a megaelectronvolt electron beam with a bunch length shorter than 100 fs could be realized with an ultrafast (≤30 fs), intense (≥1019 W/cm2) laser pulse.展开更多
The collective interaction between intense ion beams and plasmas is studied by simulations and experiments,where an intense proton beam produced by a short pulse laser is injected into a pre-ionized gas.It is found th...The collective interaction between intense ion beams and plasmas is studied by simulations and experiments,where an intense proton beam produced by a short pulse laser is injected into a pre-ionized gas.It is found that,depending on its current density,collective effects can significantly alter the propagated ion beam and the stopping power.The quantitative agreement that is found between theories and experiments constitutes the first validation of the collective interaction theory.The effects in the interaction between intense ion beams and background gas plasmas are of importance for the design of laser fusion reactors as well as for beam physics.展开更多
基金National 863-803 Project of China(No.2002AA834020)
文摘The propagation characteristics of the beam under various initial conditions are in-vestigated by means of PIC method.The influences of density modulation and velocity modulationon the propagation characteristics are discussed and compared.The results reveal that by chang-iug the amplitude of the two kinds of modulations and the phase difference between them,the
基金This work was partially supported by the Outstanding Talents Program of the Chinese Academy of Sciences.
文摘We present a new mechanism of energy gain of electrons accelerated by a laser pulse. It is shown that when the intensity of an Tiltrafast intense laser pulse decreases rapidly along the direction of propagation, electrons leaving the pulse experience an action of ponderomotive deceleration at the descending part of a lower-intensity laser field than acceleration at the ascending part of a high-intensity field, thus gain net energy from the pulse and move directly forward. By means of such a mechanism, a megaelectronvolt electron beam with a bunch length shorter than 100 fs could be realized with an ultrafast (≤30 fs), intense (≥1019 W/cm2) laser pulse.
基金We acknowledge the support of the LULI technical teams and support from Grant No.E1127 from Region Ile-de-France.S.N.C is supported by the National Science Foundation under Grant No.OISE-1064468This work was partly done within the LABEX Plas@Par project and supported by Grant No.11-IDEX-0004-02 and ANR-17-CE30-0026-Pinnacle from Agence Nationale de la Recherche+2 种基金It has received funding from the European Union's Horizon 2020 Research and Innovation programme under LASERLAB-EUROPE grant agreement No.654148 Laserlab-EuropeThis work has been carried out within the framework of the EUROfusion Consortium and has received funding,through the ToIFE,from the European Union's Horizon 2020 research and innovation programme under Grant Agreement No.633053The views and opinions expressed herein do not necessarily reflect those of the European Commission.This work was also supported in part by JSPS KAKENHI Grant No.15H03758.
文摘The collective interaction between intense ion beams and plasmas is studied by simulations and experiments,where an intense proton beam produced by a short pulse laser is injected into a pre-ionized gas.It is found that,depending on its current density,collective effects can significantly alter the propagated ion beam and the stopping power.The quantitative agreement that is found between theories and experiments constitutes the first validation of the collective interaction theory.The effects in the interaction between intense ion beams and background gas plasmas are of importance for the design of laser fusion reactors as well as for beam physics.
