الفوضى، الانتشار، وركوب الأمواج: ديناميكيات الجسيمات في الموجات الكهرومغناطيسية غير الخطية ✛ ✦

الملخص الأصلي

كما كتبه المؤلفون، بالإنجليزية arXiv:2607.04359

We investigate the dynamics of charged particles interacting with ultra-intense electromagnetic X-modes in strongly magnetized plasmas. We demonstrate that particle motion becomes chaotic for relative wave intensities $$\delta = B_w/B_0 \gtrsim 0.25$$ (not above the field reversal threshold $$\delta \geq 1$$). The transition to chaos occurs via the Chirikov resonance overlap mechanism and the related destruction of Kolmogorov-Arnold-Moser (KAM) tori. The maximum Lyapunov exponent increases logarithmically with $$\delta$$, even though the unmagnetized $$\delta \to \infty$$ limit is strictly integrable. In the $$\delta \gg 1$$ regime, incomplete re-laminarization of the phase space flow leads to two distinct populations: (i) the majority of particles undergoing stochastic diffusion, and (ii) a fraction of particles that become phase-locked with the wave, experiencing macroscopic intermittent surfing (L\'evy flights). The 1D Particle-In-Cell simulations using the EPOCH code in the highly magnetized ($$\sigma \gg 1$$) and under-dense regime are generally consistent with the Hamiltonian single-particle theory. The dissipation fraction of the initial EM energy remains mild.