Direct observation of Wave Particle interaction in PHASMA Experiments

Wave-particle interactions in plasma involve the transfer of energy and momentum from large-scale processes such as turbulence, magnetic reconnection, and instabilities to smaller scales, where the energy can dissipate, resulting in bulk heating and energetic particle generation. Here we present a study of wave-particle interactions in a collisionless, low-beta flux rope plasma generated in PHAse Space MApping (PHASMA) device. PHASMA is designed to study magnetic reconnection induced by interacting two flux ropes. Using incoherent Thomson scattering, electron velocity distribution functions (EVDFs) are measured and a linear array of Langmuir probes detects propagating plasma waves. Non-Maxwellian features in the EVDF, including a cold electron beam near the resonant wave phase velocity (v = ω/k), indicate strong coupling between waves and particles. We employ wave-particle correlation methods to analyze these interactions, revealing resonant interactions that facilitate energy transfer and momentum exchange within the plasma.