Simulations of pulsed-power driven magnetic reconnection experiments


Monday, April 29, 2024
11:00 - 12:00


Pulsed-power technology is used to generate HEDP (high energy density physics) conditions in the laboratory. The largest pulsed-power device is the Z facility in Sandia National Laboratories, which delivers a rapid current pulse of up to 80 TW peak power to a load [1]. A frequently used load is the “wire array”, a cylindrical array of fine metallic wires that form an ablated surface or “coronal” plasma due to the large current. The resultant magnetic field configuration acts to accelerate the plasma radially inwards (in the standard wire array configuration) or outwards (in the inverse configuration) from the array axis.Recent experiments on the Z facility used two adjacent inverse wire arrays to perform magnetic reconnection experiments. Magnetic reconnection is a phenomenon where opposingly oriented magnetic fields are brought together by inflows and undergo a change in topology. The plasma streams from each wire array carry frozen-in magnetic fields, thus forming a reconnection layer where they interact. Plasma parameters of these flows are typically n_e∼10^18/cm^3 and T_e∼10 eV, i.e. a relatively collisional plasma with respect to the layer length, L∼10 cm.At early times during the rising current pulse, the Lundquist number (S=LV_A/η) of the plasma flows is S∼10^4, making it susceptible to “plasmoid” formation [2]. At later times (and higher currents), simulations predict that the reconnection layer undergoes radiative cooling, such that the Lunqduist number drops to S∼10^2, i.e. a regime where plasmoids are no longer formed.
This talk will overview the basics of pulsed-power technology and the formation of plasma using wire array loads. The use of inverse wire arrays for magnetic reconnection experiments will be overviewed, and finally simulation studies of the experiment using a resistive-MHD code will be discussed.

[1] D. Sinars, et al. (2020). Phys. Plasmas, 27 (7): 070501.
[2] Ji, H., & Daughton, W. (2011). Physics of Plasmas, 18(11), 111207.




Science Park 904

Room number



astrophysics, computational physics


Nikita (Nik) Chaturvedi (postdoc from the Centre for Inertial Fusion Studies (CIFS) at Imperial College, London)

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