Enhanced ion acceleration in the ultra-intense laser driven magnetized collisionless shocks

Autor: Wen-shuai Zhang, Hong-bo Cai, Liu-lei Wei, Jian-min Tian, Shao-ping Zhu
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: New Journal of Physics, Vol 21, Iss 4, p 043026 (2019)
Druh dokumentu: article
ISSN: 1367-2630
DOI: 10.1088/1367-2630/ab1443
Popis: The effect of an externally applied magnetic field on the ion acceleration by laser-driven collisionless shocks is examined by means of multi-dimensional particle-in-cell simulations. For the interaction of ultra-intense sub-picosecond laser pulses with the near-relativistic critical-density plasma, the longitudinal transport of the laser generated fast electrons are significantly inhibited by the kilo-Tesla (kT) level transverse magnetic field, resulting in a thermal pressure which significantly exceeds the laser radiation pressure in the hot electron accumulation region. As a result, the accumulated plasma expands into the vacuum and leads to acceleration of a supersonic plasma flow in the opposite direction through the rocket effect, which streams into the target and drives a supercritical magnetized collisionless shock. In comparison with the case without the external magnetic field, where an electrostatic collisionless shock can be driven, the energy flux of the shock accelerated quasi-monoenergetic ion beam is considerably increased by an order of magnitude due to the strength enhancement of the magnetized shock.
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