DC trains and Pc3s: Source effects in mid‐latitude geomagnetic transfer functions
DC trains and Pc3s: Source effects in mid‐latitude geomagnetic transfer functions
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直流列车和 Pc3：中纬度地磁传递函数的源效应
DOI：
10.1029/1999gl008369
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发表时间：
2000
影响因子：
5.2
通讯作者：
H. Morrison
中科院分区：
文献类型：
--
作者：
G. Egbert;M. Eisel;O. Boyd;H. Morrison
来自加利福尼亚州旧金山东南 150 公里和 300 公里处的两个地点的大地电磁 (MT) 数据（地磁偶极子纬度：43 度，L 约为 1.9）表明，在 10-30 秒的周期范围内，通常的 MT 假设空间均匀的外部磁场在很大程度上被违反。站间传输函数表现出较大的系统时间变化，这与两个不同来源的组合一致：旧金山湾区快速交通 (BART) 直流电气铁路产生的电磁噪声和 Pc3 地磁脉动。数据表明，某些 PC 活动实际上可能是由 BART 激发的。
Magnetotelluric (MT) data from two sites 150 and 300 km southeast of San Francisco, California (geomagnetic dipole latitude: 43 degrees, L approximately 1.9) show that the usual MT assumption of spatially uniform external magnetic fields is violated to a significant degree in the period range 10–30 s. Inter‐station transfer functions exhibit large systematic temporal variations which are consistent with a combination of two distinct sources: electromagnetic noise due to the San Francisco Bay Area Rapid Transit (BART) DC electric railway, and Pc3 geomagnetic pulsations. There is a suggestion in the data that some of the Pc activity may actually be excited by BART.