Relativistic Particle Acceleration due to Magnetically Driven Reconnection at low-β using Laser-Powered Capacitive Coils

Magnetic Reconnection is the ubiquitous astrophysical process in which a plasma rapidly converts magnetic field energy into a combination of flow energy, thermal energy and non-thermal energetic particles. In extreme astrophysical environments like black holes and neutron stars, acceleration mechanisms (including Fermi acceleration, betatron acceleration, reconnection electric field acceleration and electric field acceleration across magnetic fields) can accelerate particles in magnetic reconnection to a relativistic regime. Only recently, [1] has this environment been experimentally studied using short-pulse lasers to drive parallel currents in a capacitively coupled quasi-axisymmetric laser coil system. This process achieves ~150 Tesla and σ_e = 10 relativistic reconnection. We further demonstrate an empirically derived relativistic scaling law for this astrophysical reconnection regime. Corroborating with 3D and 2D VPIC simulation, preliminary experimental results are validated against these analytic models.

[1]: A. Chien, L. Gao, S. Zhang, H. Ji, E. G. Blackman, W. Daughton, A. Stanier, A. Le, F. Guo, R. Follett, H. Chen, G. Fiksel, G. Bleotu, R. C. Cauble, S. N. Chen, A. Fazzini, K. Flippo, O. French, D. H. Froula, J. Fuchs, S. Fujioka, K. Hill, S. Klein, C. Kuranz, P. Nilson, A. Rasmus, and R. Takizawa, “Non-thermal electron acceleration from magnetically driven reconnection in a laboratory plasma,” Nature Physics 19, 254–262 (2023)