MESSENGER observations of the energization and heating of protons in the near-Mercury magnetotail
MESSENGER observations of the energization and heating of protons in the near-Mercury magnetotail
复制标题
MESSENGER 对近水星磁尾中质子的激发和加热的观测
DOI：
10.1002/2017gl074276
复制
发表时间：
2017
影响因子：
5.2
通讯作者：
Wan W. X.
中科院分区：
文献类型：
--
作者：
Sun W. J.;Raines J. M.;Fu S. Y.;Slavin J. A.;Wei Y.;Poh G. K.;Pu Z. Y.;Yao Z. H.;Zong Q. G.;Wan W. X.
近水星尾部质子的冷却和加热过程通过水星表面、空间环境、地球化学和测距（信使号）观测进行了研究。在一个案例研究中，观察到超热质子粒子通量（STPF）和质子温度在近水星亚暴偶极过程中明显增强，表明质子的蒸发和加热过程。近水星中心等离子体片中的STPF和质子温度分布显示黎明-黄昏不对称性，黎明侧等离子体片中的值较高，即，午夜后，比在黄昏，即，午夜前进一步的研究表明，这些不对称性在水星磁层的活跃期比平静期更为突出。在theZMSM组件中的磁场变化显示出类似的功能，在活跃期期间，黎明侧的变化比黄昏侧更突出。我们认为质子分布的黎明-黄昏不对称性可能是由于水星磁尾黎明一侧引发了更多的亚暴偶极。
The energization and heating processes for protons in the near‐Mercury tail are examined with MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) observations. In a case study, suprathermal proton particle flux (STPF) and proton temperature are observed to be clearly enhanced during near‐Mercury substorm dipolarizations, indicating the proton energization and heating processes. STPF and proton temperature distributions in near‐Mercury central plasma sheets display dawn‐dusk asymmetries, with higher values in the dawnside plasma sheet, i.e., postmidnight, than in the duskside, i.e., premidnight. Further investigations reveal that these asymmetries are more prominent during active periods in Mercury's magnetosphere, as compared to quiet periods. Magnetic field variations in theZMSMcomponent display a similar feature, with variations being more prominent on the dawnside than the duskside during active periods. We propose that the dawn‐dusk asymmetry in the distributions of protons could be due to the fact that more substorm dipolarizations were initiated on the dawnside of Mercury's magnetotail.