Collisionless Weibel shocks: Full formation mechanism and timing

Journal Article · Tue Jul 15 04:00:00 EDT 2014 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4886121· OSTI ID:22304078

Bret, A. ^[1]; Stockem, A. ^[2]; Narayan, R. ^[3]; Silva, L. O. ^[2]

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1. ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain)
2. GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon (Portugal)
3. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51 Cambridge, Massachusetts 02138 (United States)

Collisionless shocks in plasmas play an important role in space physics (Earth's bow shock) and astrophysics (supernova remnants, relativistic jets, gamma-ray bursts, high energy cosmic rays). While the formation of a fluid shock through the steepening of a large amplitude sound wave has been understood for long, there is currently no detailed picture of the mechanism responsible for the formation of a collisionless shock. We unravel the physical mechanism at work and show that an electromagnetic Weibel shock always forms when two relativistic collisionless, initially unmagnetized, plasma shells encounter. The predicted shock formation time is in good agreement with 2D and 3D particle-in-cell simulations of counterstreaming pair plasmas. By predicting the shock formation time, experimental setups aiming at producing such shocks can be optimised to favourable conditions.

• OSTI ID: 22304078
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 7 Vol. 21; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ASTROPHYSICS
COSMIC GAMMA BURSTS
PLASMA
RELATIVISTIC RANGE
SHOCK WAVES
SIMULATION
SOUND WAVES
SUPERNOVA REMNANTS