Relationship between large horizontal electric fields and auroral arc elements
Relationship between large horizontal electric fields and auroral arc elements
复制标题
水平大电场与极光弧要素的关系
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
I. McCrea
中科院分区：
文献类型：
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作者：
B. Lanchester;K. Kaila;I. McCrea
高时间分辨率的光学测量在磁天顶相比，欧洲非相干散射（EISCAT）的电子密度在0.2秒的分辨率和水平电场测量在278公里的分辨率为9秒的字段对齐的测量。在一次事件中，在壮观的极光解体后20分钟，一个狭窄而活跃的弧元素系统向南移动到磁天顶，并在那里停留了几分钟。在一个非常靠近雷达波束的窄弧元素中，在30 s的活动间隔期间，发现3 s分辨率的电场矢量非常大（高达400 mV m−1），并指向弧中的明亮光学特征，这些特征沿其长度沿着移动。有人提出，大电场是短暂的，并直接与粒子沉淀，导致明亮的极光弧元素的功能。
High time resolution optical measurements in the magnetic zenith are compared with European Incoherent Scatter (EISCAT) field-aligned measurements of electron density at 0.2-s resolution and with horizontal electric field measurements made at 278 km with resolution of 9 s. In one event, 20 min after a spectacular auroral breakup, a system of narrow and active arc elements moved southward into the magnetic zenith, where it remained for several minutes. During a 30-s interval of activity in a narrow arc element very close to the radar beam, the electric field vectors at 3-s resolution were found to be extremely large (up to 400 mV m−1) and to point toward the bright optical features in the arc, which moved along its length. It is proposed that the large electric fields are short-lived and are directly associated with the particle precipitation that causes the bright features in auroral arc elements.