Electron acceleration and small scale coherent structures formation by an Alfvén wave propagating in coronal interplume region

Abstract

We use 2.5-D electromagnetic particle-in-cell simulation code to investigate the acceleration of electrons in solar coronal holes through the interaction of Alfvén waves with an interplume region. The interplume is modeled by a cavity density gradients that are perpendicular to the background magnetic field. The aim is to contribute to explain the observation of suprathermal electrons under relatively quiet sun. Simulations show that Alfvén waves in interaction with the interplume region gives rise to a strong local electric field that accelerates electrons in the direction parallel to the background magnetic field. Suprathermal electron beams and small-scale coherent structures are observed within interplume of strong density gradients. These features result from non linear evolution of the electron beam plasma instability.

9 pages, 9 figures, Published in Astronomische Nachrichten, 08/2017

References in corpus (5)

• Magnetic Landscape of Sun's Polar Region
• First direct measurements of transverse waves in solar polar plumes using SDO/AIA
• Accelerating waves in polar coronal holes as seen by EIS and SUMER
• A minimal model of parallel electric field generation in a transversely inhomogeneous plasma
• Collisionless, phase-mixed, dispersive, Gaussian Alfven pulse in transversely inhomogeneous plasma