ISEE 1 observations of electrostatic ion cyclotron waves in association with ion beams on auroral field lines from ∼2.5 to 4.5 RE
ISEE 1 observations of electrostatic ion cyclotron waves in association with ion beams on auroral field lines from ∼2.5 to 4.5 RE
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ISEE 1 观测到与极光场线上离子束相关的静电离子回旋波，从 ~2.5 到 4.5 RE
DOI：
10.1029/91ja00378
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发表时间：
1991
影响因子：
--
通讯作者：
E. Ungstrup
中科院分区：
文献类型：
--
作者：
C. Cattell;F. Mozer;I. Roth;R. R. Anderson;R. Elphic;W. Lennartsson;E. Ungstrup
1981年6月19日午夜，ISEE 1卫星在{大约}2.5 - 4.5 R{sub E}的径向距离上穿越极光场线时，观测到{大约}1.2 f{sub cH}的准单色波，其中f{sub cH}是氢回旋加速器的频率。波垂直于磁场极化（k{sub {parallel}}/k{sub {vertical}} {le} 0.2）。此外，在略高于氦和氧回旋加速器频率的地方也有波。波发生在密度降低的区域内（{大约}0.1 - 0.2/cm{sup 3}），电子温度大于离子温度，向上流动的氢和氧束，以及由静电冲击包围的弱场对准电流。波浪特征和关联与S3-3卫星在较低海拔观测到的相似。比较了观测到的H{sup +}和O{sup +}光束、场向电流、密度和温度，以及静电离子回旋波和H{sup +}{负}O{sup +}双流不稳定性的线性理论。观测到的波的特征与电流驱动模式最为一致。此外，利用观测参数对线性色散关系进行了数值研究，结果表明，平行和倾斜两流模式以及离子束驱动模式都是稳定的，而倾斜电流»驱动模式则是不稳定的。O{sup +}和H{sup +}分布提供了与局部静电离子回旋波相互作用和卫星以下高度H{sup +}{负}O{sup +}两流不稳定性的证据。«少
Quasi-monochromatic waves at {approximately}1.2 f{sub cH}, where f{sub cH} is the hydrogen cyclotron frequency, were observed as the ISEE 1 satellite traversed auroral field lines at radial distances of {approximately}2.5 - 4.5 R{sub E} near midnight on June 19, 1981. The waves were polarized perpendicular to the magnetic field (k{sub {parallel}}/k{sub {perpendicular}} {le} 0.2). In addition, there were waves at slightly above both the helium and the oxygen cyclotron frequencies. The waves occurred within a region of reduced density ({approximately}0.1 - 0.2/cm{sup 3}) with the electron temperature greater than the ion temperature, upflowing hydrogen and oxygen beams, and weak field-aligned currents bounded by electrostatic shocks. The wave characteristics and associations were similar to those observed at lower altitudes by the S3-3 satellite. Comparisons were made between the observed H{sup +} and O{sup +} beams, field-aligned currents, densities and temperatures, and linear theories of electrostatic ion cyclotron waves and H{sup +}{minus}O{sup +} two-stream instabilities. The features of the observed waves are most consistent with the current-driven mode. In addition, numerical studies of the linear dispersion relation, using parameters based on the observations, showed that both the parallel and oblique two-stream modes and the ion-beam driven modes were stable while oblique currentmore » driven modes were unstable. The O{sup +} and H{sup +} distributions provide evidence for interactions with local electrostatic ion cyclotron waves and for the H{sup +}{minus}O{sup +} two-stream instability at altitudes below the satellite.« less