Regimes of magnetic reconnection in colliding laser-produced magnetized plasma bubbles

Journal Article · Fri Sep 07 00:00:00 EDT 2018 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.5044547· OSTI ID:1472095

Lezhnin, K. V. ^[1]; Fox, W.  ^[2]; Matteucci, J. ^[3]; Schaeffer, D. B. ^[3]; Bhattacharjee, A. ^[2]; Rosenberg, M. J. ^[4]; Germaschewski, K.  ^[5]

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1. Princeton Univ., Princeton, NJ (United States); National Research Nuclear Univ. MEPhI, Moscow (Russia)
2. Princeton Univ., Princeton, NJ (United States); Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
3. Princeton Univ., Princeton, NJ (United States)
4. Univ. of Rochester, Rochester, NY (United States)
5. Univ. of New Hampshire, Durham, NH (United States)

Here, we conduct a multiparametric study of driven magnetic reconnection relevant to recent experiments on colliding magnetized laser-produced plasmas using particle-in-cell simulations. Varying the background plasma density, plasma resistivity, and plasma bubble geometry, the 2D simulations demonstrate a rich variety of reconnection behaviors and show the coupling between magnetic reconnection and the global hydrodynamical evolution of the system. We consider both the collision between two radially expanding bubbles where reconnection is seeded by the pre-existing X-point and the collision between two flows in a quasi-1D geometry with initially anti-parallel fields where reconnection must be initiated by the tearing instability. At a baseline case of low-collisionality and low background density, the current sheet is strongly compressed to below scale of the ion-skin-depth scale, and rapid, multi-plasmoid reconnection results. Increasing the plasma resistivity, we observe a collisional slow-down of reconnection and stabilization of plasmoid instability for Lundquist numbers less than approximately S ~10³. Second, increasing the background plasma density modifies the compressibility of the plasma and can also slow down or even prevent reconnection, even in completely collisionless regimes, by preventing the current sheet from thinning down to the scale of the ion-skin depth. These results have implications for understanding recent and future experiments, and signatures for these processes for proton-radiography diagnostics of these experiments are discussed.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF); Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: AC05-00OR22725; SC0008655; SC0016249
• OSTI ID: 1472095
• Alternate ID(s): OSTI ID: 1469044
• Journal Information: Physics of Plasmas, Vol. 25, Issue 9; ISSN 1070-664X
• Publisher: American Institute of Physics (AIP)
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
Magnetic reconnection
Magnetic fields
Plasma sheets
Particle-in-cell method