Dense GeV electron-positron pairs generated by lasers in near-critical-density plasmas.

ABSTRACT: Pair production can be triggered by high-intensity lasers via the Breit-Wheeler process. However, the straightforward laser-laser colliding for copious numbers of pair creation requires light intensities several orders of magnitude higher than possible with the ongoing laser facilities. Despite the numerous proposed approaches, creating high-energy-density pair plasmas in laboratories is still challenging. Here we present an all-optical scheme for overdense pair production by two counter-propagating lasers irradiating near-critical-density plasmas at only ?1022?W?cm-2. In this scheme, bright ?-rays are generated by radiation-trapped electrons oscillating in the laser fields. The dense ?-photons then collide with the focused counter-propagating lasers to initiate the multi-photon Breit-Wheeler process. Particle-in-cell simulations indicate that one may generate a high-yield (1.05 × 1011) overdense (4 × 1022?cm-3) GeV positron beam using 10 PW scale lasers. Such a bright pair source has many practical applications and could be basis for future compact high-luminosity electron-positron colliders.

SUBMITTER: Zhu XL 

PROVIDER: S-EPMC5171869 | biostudies-other | 2016 Dec

REPOSITORIES: biostudies-other