Tearing instability and particle energization in collisionless, suprathermal plasmas

• Applicant: Professorin Dr. Maria Elena Innocenti
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 544893192

The aptly called tearing instability tears up current sheets (CSs) in a number of plasmoids separated by reconnection X points, and turns a steady-state CS into the locus of violent magnetic- to-kinetic energy conversion and particle heating and acceleration. Understanding under which conditions CSs are unstable to the tearing instability and how efficiently it develops (Objective 1) is therefore essential for a complete picture of energy dynamics in space and astrophysical plasmas. In doing so, one should also keep into account that most heliospheric plasmas are collisionless: since thermalization mechanisms are inefficient, most observed velocity distribution functions (VDFs) depart quite significant from thermal (Maxwellian) distributions, and are better modeled with suprathermal (kappa) distributions. This affects both instability threshold and growth rates (Objective 2). Furthermore, competing/ concurrent instabilities develop together with the tearing instability and participate in particle heating and acceleration (Objective 3). Within this project, we intend to extend existing knowledge of particle energization via tearing- triggered magnetic reconnection to realistic scenarios that factor in the elements mentioned above. We will do so with a two-pronged theoretical and numerical approach.

• DFG Programme: Research Grants
• International Connection: Belgium
• Cooperation Partner: Professor Marian Lazar, Ph.D.