Gamma flashes from relativistic electron-positron plasma droplets

Relativistic Expansion of Electron-Positron-Photon Plasma Droplets and Photon Emission

The expansion dynamics of hot electron-positron-photon plasma droplets is dealt with within relativistic hydrodynamics. Such droplets, envisaged to be created in future experiments by irradiating thin foils with counter-propagating ultra-intense laser beams, are sources of flashes of gamma radiation. Warm electron-positron plasma droplets may be identified and characterized by a broadened 511 keV line.

双激光与微丝相互作用中的阿秒伽马射线闪光和电子-正电子对

Attosecond gamma-ray flashes and electron-positron pairs in dyadic laser interaction with micro-wire

本研究提出利用两束高功率激光与微丝靶作用的可调谐方案，先通过径向偏振激光产生低横向动量的短脉冲高电荷电子束团，再与反向激光碰撞，可生成高准直超高亮度阿秒GeV级γ射线及固体密度级电子-正电子对，为高能粒子源研究提供新途径。

Collimated GeV attosecond electron-positron bunches from a plasma channel driven by 10 PW lasers

High-energy positrons and bright γ-ray sources are unique both for fundamental research and practical applications. However, GeV electron-positron pair jets and γ-ray flashes are still hardly produced in laboratories. Here we demonstrate that, by irradiating two 10 PW-scale laser pulses onto a near-critical density plasma channel, highly-directional GeV electron-positron pairs and bright γ-ray beams can be efficiently generated. Three-dimensional particle-in-cell simulations show that GeV positron jets show high density (8*10^21/cm^3), attosecond duration (400 as) and a divergence angle of 14°…

Electron Acceleration Mechanisms in Thunderstorms

Thunderstorms produce strong electric fields over regions on the order of kilometer. The corresponding electric potential differences are on the order of 100 MV. Secondary cosmic rays reaching these regions may be significantly accelerated and even amplified in relativistic runaway avalanche processes. These phenomena lead to enhancements of the high-energy background radiation observed by detectors on the ground and on board aircraft. Moreover, intense submillisecond gamma-ray bursts named terrestrial gamma-ray flashes (TGFs) produced in thunderstorms are detected from low Earth orbit satelli…

Modeling the relativistic runaway electron avalanche and the feedback mechanism with GEANT4

This paper presents the first study that uses the GEometry ANd Tracking 4 (GEANT4) toolkit to do quantitative comparisons with other modelling results related to the production of Terrestrial Gamma-ray Flashes (TGFs) and high-energy particle emission from thunderstorms. We will study the Relativistic Runaway Electron Avalanche (RREA) and the relativistic feedback process, as well as the production of bremsstrahlung photons from Runaway Electrons (REs). The Monte Carlo (MC) simulations take into account the effects of electron ionisation, electron by electron (Møller) and electron by positron (…