Details

Autor(en) / Beteiligte

• Xie, Yi
• Wang, Rongsheng
• Wang, Shimou
• Li, Xinmin
• Gao, Xinliang
• Lu, San

Titel

Suprathermal Ions Observed Inside a Magnetic Flux Rope in the Earth's Magnetotail

Ist Teil von

• Journal of geophysical research. Space physics, 2023-08, Vol.128 (8), p.n/a

Ort / Verlag

Washington: Blackwell Publishing Ltd

Erscheinungsjahr

2023

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• Suprathermal ions have not been observed inside magnetic flux ropes, although energetic electrons have been extensively detected and were thought to be accelerated inside magnetic flux ropes. In this paper, we present the first observation of the suprathermal ions inside a magnetic flux rope in the Earth's magnetotail with a spatial‐scale of tens of ion inertial length. This flux rope was propagating earthward, and its leading part was substantially compressed while its trailing part was significantly stretched. The suprathermal ions can be detected inside the whole flux rope and displayed distinct pitch angle distributions between its leading and trailing parts. In the leading part, the ion fluxes were enhanced primarily in the direction perpendicular to the magnetic field in the all measured energy range, while the ion fluxes increased in the parallel and antiparallel directions in the trailing parts. A large flow vortex was observed immediately behind the flux rope, consistent with Kármán vortex street. The observation suggested that a flux rope even with a large scale can still be highly dynamic, and the charged particles can be significantly accelerated during the flux rope evolution in magnetic reconnection. Key Points A large‐scale flux rope with distinct magnetic field configurations between the leading and trailing parts was observed in the magnetotail Ions can be accelerated to 178 keV within the flux rope, display mainly perpendicular in the leading part and field‐aligned in the trailing part Intense current layers were detected at the leading edge and the center of the flux rope