Reconnection acceleration in Saturn's dayside magnetodisc : a multicase study with Cassini

Guo, R. L. and Yao, Z. H. and Sergis, N. and Wei, Y. and Mitchell, D. G. and Roussos, E. and Palmaerts, B. and Dunn, W.R. and Radioti, Aikaterini and Ray, Licia C and Coates, A.J. and Grodent, D. and Arridge, Christopher Stephen and Kollmann, P. and Krupp, Norbert and Waite, J.H. and Dougherty, M.K. and Burch, J.L. and Wan, W.X. (2018) Reconnection acceleration in Saturn's dayside magnetodisc : a multicase study with Cassini. The Astrophysical Journal, 868 (2): L23. ISSN 0004-637X

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Recently, rotationally driven magnetic reconnection was firstly discovered in Saturn’s dayside magnetosphere (Guo et al. 2018). This newly confirmed process could potentially drive bursty phenomena at Saturn, i.e., pulsating energetic particles and auroral emissions. Using Cassini’s measurements of magnetic fields and charged particles, we investigate particle acceleration features during three magnetic reconnection events observed in Saturn’s dayside magnetodisc. The results suggest that the rotationally driven reconnection process plays a key role in producing energetic electrons (up to 100 keV) and ions (several hundreds of keV). In particular, we find that energetic oxygen ions are locally accelerated at all three reconnection sites. Isolated, multiple reconnection sites were recorded in succession during an interval lasting for much less than one Saturn rotation period. Moreover, a secondary magnetic island is reported for the first time at the dayside, collectively suggesting that the reconnection process is not steady and could be ‘drizzle-like’. This study demonstrates the fundamental importance of internally driven magnetic reconnection in accelerating particles in Saturn’s dayside magnetosphere, and likewise in the rapidly rotating Jovian magnetosphere and beyond.

Item Type:
Journal Article
Journal or Publication Title:
The Astrophysical Journal
Uncontrolled Keywords:
?? astronomy and astrophysicsspace and planetary science ??
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Deposited On:
08 Nov 2018 10:04
Last Modified:
25 Nov 2023 00:24