| 1. |
- Efimenko, E., et al.
(författare)
-
Extreme plasma states in laser-governed vacuum breakdown
- 2018
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 8:1
-
Tidskriftsartikel (refereegranskat)abstract
- Triggering vacuum breakdown at laser facility is expected to provide rapid electron-positron p air production for studies in laboratory astrophysics and fundamental physics. However, the density of the produced plasma may cease to increase at a relativistic critical density, when the plasma becomes opaque. Here, we identify the opportunity of breaking this limit using optimal beam configuration of petawatt-class lasers. Tightly focused laser fields allow generating plasma in a small focal volume much less than λ 3 and creating extreme plasma states in terms of density and produced currents. These states can be regarded to be a new object of nonlinear plasma physics. Using 3D QED-PIC simulations we demonstrate a possibility of reaching densities over 10 25 cm -3, which is an order of magnitude higher than expected earlier. Controlling the process via initial target parameters provides an opportunity to reach the discovered plasma states at the upcoming laser facilities.
|
|
| 2. |
- Gonoskov, Arkady, 1984, et al.
(författare)
-
Extended particle-in-cell schemes for physics in ultrastrong laser fields : Review and developments
- 2015
-
Ingår i: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. - 1539-3755 .- 1550-2376. ; 92:2
-
Tidskriftsartikel (refereegranskat)abstract
- We review common extensions of particle-in-cell (PIC) schemes which account for strong field phenomena in laser-plasma interactions. After describing the physical processes of interest and their numerical implementation, we provide solutions for several associated methodological and algorithmic problems. We propose a modified event generator that precisely models the entire spectrum of incoherent particle emission without any low-energy cutoff, and which imposes close to the weakest possible demands on the numerical time step. Based on this, we also develop an adaptive event generator that subdivides the time step for locally resolving QED events, allowing for efficient simulation of cascades. Further, we present a unified technical interface for including the processes of interest in different PIC implementations. Two PIC codes which support this interface, PICADOR and ELMIS, are also briefly reviewed.
|
|
| 3. |
- Gonoskov, Arkady, 1984, et al.
(författare)
-
Ultrabright GeV Photon Source via Controlled Electromagnetic Cascades in Laser-Dipole Waves
- 2017
-
Ingår i: Physical Review X. - 2160-3308. ; 7:4
-
Tidskriftsartikel (refereegranskat)abstract
- Electromagnetic cascades have the potential to act as a high-energy photon source of unprecedented brightness. Such a source would offer new experimental possibilities in fundamental science, but in the cascade process radiation reaction and rapid electron-positron plasma production seemingly restrict the efficient production of photons to sub-GeV energies. Here, we show how to overcome these energetic restrictions and how to create a directed GeV photon source, with unique capabilities as compared to existing sources. Our new source concept is based on a controlled interplay between the cascade and anomalous radiative trapping. Using specially designed advanced numerical models supported with analytical estimates, we demonstrate that the concept becomes feasible at laser powers of around 7 PW, which is accessible at soon-to-be-available facilities. A higher peak power of 40 PW can provide 10(9) photons with GeV energies in a well-collimated 3-fs beam, achieving peak brilliance 9 x 10(24) ph s(-1) mrad(-2) mm(-2)/0.1%BW.
|
|
| 4. |
- Meyerov, I., et al.
(författare)
-
Hybrid CPU + Xeon Phi implementation of the Particle-in-Cell method for plasma simulation
- 2016
-
Ingår i: Supercomputing Frontiers and Innovations. - : FSAEIHE South Ural State University (National Research University). - 2313-8734 .- 2409-6008. ; 3:3, s. 5-10
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents experimental results of Particle-in-Cell plasma simulation on a hybrid system with CPUs and Intel Xeon Phi coprocessors. We consider simulation of two relevant laserdriven particle acceleration regimes using the Particle-in-Cell code PICADOR. On a node of a cluster with 2 CPUs and 2 Xeon Phi coprocessors the hybrid CPU + Xeon Phi configuration allows to fully utilize the computational resources of the node. It outperforms both CPU-only and Xeon Phi-only configurations with the speedups between 1.36 x and 1.68 x.
|
|
| 5. |
- Muraviev, A. A., et al.
(författare)
-
Generation of current sheets and giant quasistatic magnetic fields at the ionization of vacuum in extremely strong light fields
- 2015
-
Ingår i: JETP Letters. - 1090-6487 .- 0021-3640. ; 102:3, s. 148-153
-
Tidskriftsartikel (refereegranskat)abstract
- The self-consistent dynamics of an electron–positron plasma, which is formed during the generation of quantum-electrodynamic cascades, in a superstrong field of counterpropagating linearly polarized waves is examined. It is shown that the formation of thin (on a wavelength scale) current sheets which generate quasistatic magnetic fields comparable to the corresponding fields of incident waves plays an important role in the dynamics of a cascade for fields above a certain threshold. The fraction of the laser energy transformed into the energy of quasistatic magnetic fields can exceed 20%.
|
|
