<p>Understanding the balance between charged particle acceleration and loss is central to radiation belt research. Jupiter’s Galilean moons orbit within its intense radiation environment and can act both as sources and sinks of energetic particles. Using observations from the Juno spacecraft, we identify large-scale depletions of energetic electrons along Europa’s orbit. These depletions are too deep to result from direct absorption by the moon alone. Here we show that rapid electron losses, occurring within a timescale shorter than Jupiter’s rotation, are driven by pitch angle scattering via whistler-mode waves co-located with Europa’s orbit. This suggests that Europa maintains a plasma environment capable of sustaining a slot-like region, similar to the one seen in Earth’s Van Allen belts. However, this Jovian slot only partially extends along Europa’s path, implying that additional, unidentified acceleration mechanisms may act to refill the region and maintain high radiation levels close to Jupiter.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

A slot region in the magnetosphere of Jupiter

  • Minyi Long,
  • Elias Roussos,
  • Binbin Ni,
  • Qianli Ma,
  • Peter Kollmann,
  • Ruoxian Zhou,
  • George Clark,
  • Norbert Krupp,
  • Xing Cao,
  • Peng Lu,
  • Yixin Hao,
  • Shaobei Wang

摘要

Understanding the balance between charged particle acceleration and loss is central to radiation belt research. Jupiter’s Galilean moons orbit within its intense radiation environment and can act both as sources and sinks of energetic particles. Using observations from the Juno spacecraft, we identify large-scale depletions of energetic electrons along Europa’s orbit. These depletions are too deep to result from direct absorption by the moon alone. Here we show that rapid electron losses, occurring within a timescale shorter than Jupiter’s rotation, are driven by pitch angle scattering via whistler-mode waves co-located with Europa’s orbit. This suggests that Europa maintains a plasma environment capable of sustaining a slot-like region, similar to the one seen in Earth’s Van Allen belts. However, this Jovian slot only partially extends along Europa’s path, implying that additional, unidentified acceleration mechanisms may act to refill the region and maintain high radiation levels close to Jupiter.