Direct measurement of non-thermal electron acceleration from magnetically driven reconnection in a laboratory plasma - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue (Data Paper) Nature Physics Année : 2021

Direct measurement of non-thermal electron acceleration from magnetically driven reconnection in a laboratory plasma

Eric Blackman
Russ Follett
  • Fonction : Auteur
Hui Chen
Gennady Fiksel
  • Fonction : Auteur
Gabriel Bleotu
  • Fonction : Auteur
Robert Cauble
  • Fonction : Auteur
Sophia Chen
  • Fonction : Auteur
Kirk Flippo
Omar French
  • Fonction : Auteur
Dustin Froula
Shinsuke Fujioka
Philip Nilson
  • Fonction : Auteur
Alexander Rasmus
Ryunosuke Takizawa

Résumé

Magnetic reconnection rapidly converts magnetic energy into some combination of plasma flow energy, thermal energy and non-thermal energetic particles. Various reconnection acceleration mechanisms have been theoretically proposed and numerically studied in different collisionless and low-β environments, where β refers to the plasma-to-magnetic pressure ratio. These mechanisms include Fermi acceleration, betatron acceleration, parallel electric field acceleration along magnetic fields and direct acceleration by the reconnection electric field. However, none of them have been experimentally confirmed, as the direct observation of non-thermal particle acceleration in laboratory experiments has been difficult due to short Debye lengths for in situ measurements and short mean free paths for ex situ measurements. Here we report the direct measurement of accelerated non-thermal electrons from magnetically driven reconnection at low β in experiments using a laser-powered capacitor coil platform. We use kilojoule lasers to drive parallel currents to reconnect megagauss-level magnetic fields in a quasi-axisymmetric geometry. The angular dependence of the measured electron energy spectrum and the resulting accelerated energies, supported by particle-in-cell simulations, indicate that the mechanism of direct electric field acceleration by the out-of-plane reconnection electric field is at work. Scaled energies using this mechanism show direct relevance to astrophysical observations.
Fichier principal
Vignette du fichier
Chien_Nat_Phys_manuscript.pdf (4.59 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-04263752 , version 1 (29-10-2023)

Identifiants

Citer

Abraham Chien, Lan Gao, Shu Zhang, Hantao Ji, Eric Blackman, et al.. Direct measurement of non-thermal electron acceleration from magnetically driven reconnection in a laboratory plasma. Nature Physics, 2021, 19, pp.254-262. ⟨10.1038/s41567-022-01839-x⟩. ⟨hal-04263752⟩
11 Consultations
6 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More