High Power Gamma-Ray Flash Generation in Ultra Intense Laser-Plasma Interaction

When high-intensity laser interaction with matter enters the regime of dominated radiation reaction, the radiation losses open the way for producing short pulse high power gamma ray flashes. The gamma-ray pulse duration and divergence are determined by the laser pulse amplitude and by the plasma target density scale length. On the basis of theoretical analysis and particle-in-cell simulations with the radiation friction force incorporated, optimal conditions for generating a gamma-ray flash with a tailored overcritical density target are found.Comment: 12 pages, 5 figures Accepted for publication in Physical Review Letters (this http://prl.aps.org/

On extreme field limits in high power laser matter interactions: radiation dominant regimes in high intensity electromagnetic wave interaction with electrons

We discuss the key important regimes of electromagnetic field interaction with charged particles. Main attention is paid to the nonlinear Thomson/Compton scattering regime with the radiation friction and quantum electrodynamics effects taken into account. This process opens a channel of high efficiency electromagnetic energy conversion into hard electromagnetic radiation in the form of ultra short high power gamma ray flashes.Comment: 15 pages, 10 figures, invited talk presented at the SPIE-2013 conference, Prague, Czech Republic, Apr. 15, 201

Notable improvements on LWFA through precise laser wavefront tuning

Oumbarek Espinos D., Rondepierre A., Zhidkov A., et al. Notable improvements on LWFA through precise laser wavefront tuning. Scientific Reports 13, 18466 (2023); https://doi.org/10.1038/s41598-023-45737-5.Laser wakefield acceleration (LWFA) continues to grow and awaken interest worldwide, especially as in various applications it approaches performance comparable to classical accelerators. However, numerous challenges still exist until this can be a reality. The complex non-linear nature of the process of interaction between the laser and the induced plasma remains an obstacle to the widespread LWFA use as stable and reliable particle sources. It is commonly accepted that the best wavefront is a perfect Gaussian distribution. However, experimentally, this is not correct and more complicated ones can potentially give better results. in this work, the effects of tuning the laser wavefront via the controlled introduction of aberrations are explored for an LWFA accelerator using the shock injection configuration. Our experiments show the clear unique correlation between the generated beam transverse characteristics and the different input wavefronts. The electron beams stability, acceleration and injection are also significantly different. We found that in our case, the best beams were generated with a specific complex wavefront. A greater understanding of electron generation as function of the laser input is achieved thanks to this method and hopes towards a higher level of control on the electrons beams by LWFA is foreseen

On the breaking of a plasma wave in a thermal plasma: I. The structure of the density singularity

The structure of the singularity that is formed in a relativistically large amplitude plasma wave close to the wavebreaking limit is found by using a simple waterbag electron distribution function. The electron density distribution in the breaking wave has a typical "peakon" form. The maximum value of the electric field in a thermal breaking plasma is obtained and compared to the cold plasma limit. The results of computer simulations for different initial electron distribution functions are in agreement with the theoretical conclusions.Comment: 21 pages, 12 figure