Abstract—

Changes in the structure of the summer equatorial anomaly of electron density with local time and longitude at high solar activity are considered in detail according to topside sounding data from the Interkosmos-19 satellite. It is shown that the equatorial anomaly starts to develop from ~0800 LT, when the winter (southern) crest is formed. The summer (northern) crest is ~2 h behind in development. It is formed at the background of a low latitudinal foF2 maximum. In the daytime, the northern crest is ~3° farther from the geomagnetic equator than the southern one. The crest position changes greatly with longitude. A local maximum is observed in the development of the equatorial anomaly at 1400 LT. It is particularly pronounced in the Eastern Hemisphere. The foF2 value above the geomagnetic equator and anomaly intensity change with longitude at 1200–1400 LT according to the changes in the vertical plasma drift W. A local minimum is observed in the development of the equatorial anomaly at 1800 LT. The anomaly intensity then increases to a maximum 1.5–2.0 h after the evening peak in W. Longitudinal foF2 variations and the anomaly intensity in the interval 2000–2200 LT are also associated with W variations. The anomaly intensity decreases after the maximum, and the crests decrease in magnitude and move toward the equator. The foF2 maxima in the crest region of the anomaly after midnight, conversely, are farther away from the geomagnetic equator, which seems to be due to the action of the neutral wind. The equatorial anomaly has almost decayed by 0400 LT and does not manifest itself as a structure from 0500 to 0700 LT. Therefore, the well-expressed equatorial anomaly is observed from 1200 to 2400 LT at high solar activity.

中文翻译：

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根据Interkosmos-19卫星，夏至期间赤道异常结构的变化

摘要—

根据来自Interkosmos-19卫星的顶部探测数据，详细考虑了夏季太阳赤道异常的结构在高太阳活动下随当地时间和经度的变化。结果表明，当形成冬季（南部）波峰时，赤道异常从〜0800 LT开始发展。夏季（北部）波峰发育滞后约2小时。它是在低的fof 2最大值的背景下形成的。在白天，北顶离地磁赤道比南顶约3°。波峰的位置随经度变化很大。在1400 LT处，赤道异常的发展出现了局部最大值。在东半球尤为明显。该FOF地磁赤道上方的2值和异常强度随垂直等离子漂移W的变化在1200–1400 LT处随经度而变化。在1800 LT处赤道异常的发展中观察到了局部最小值。然后，在W的夜间峰值之后，异常强度增加到最大1.5–2.0 h 。纵向foF 2变化和2000-2200 LT间隔内的异常强度也与W变化有关。异常强度在最大值之后减小，并且波峰的幅度减小并移向赤道。该FOF相反，午夜后异常波峰区域的2个最大值离地磁赤道较远，这似乎是由于中性风的作用。赤道异常几乎已经衰减了0400 LT，并且没有表现为0500到0700 LT之间的结构。因此，在太阳活动高的情况下，从1200到2400 LT观察到了表达良好的赤道异常。