Auroral beam‐plasma interactions: Particle correlator investigations
Auroral beam‐plasma interactions: Particle correlator investigations
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极光束-等离子体相互作用：粒子相关器研究
DOI：
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
K. Wilhelm
中科院分区：
文献类型：
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作者：
M. Gough;P. Christiansen;K. Wilhelm
等离子体波的不稳定性可能发生在离散的极光弧之上，在那里自然加速的极光电子成分与冷的电离层等离子体相遇。在凯撒二号火箭上，通过测量0-10 kHz和0-10 MHz频率范围内高能电子通量的调制，研究了这些波粒相互作用。在远地点（700 km）附近，观察到1.4 MHz（≈fuh）的7.5 keV电子的强调制，其中df(υ)/dυ为正，刚好低于极光束速度。测量结果与朗道和回旋加速器共振与上层混合波相互作用驱动的不稳定性相一致，也与早期在低空火箭E2-B（远地点230公里）上观测到的2.65 MHz（≈fuh）调制相一致。
Plasma wave instabilities may occur above discrete auroral arcs where the natural accelerated auroral electron component meets the cold ionospheric plasma. These wave-particle interactions were studied on the CAESAR II rocket by measuring the modulations in energetic electron flux in the frequency ranges 0–10 kHz and 0–10 MHz. Near apogee (700 km) a strong modulation of 7.5 keV electrons at 1.4 MHz (≈ fuh) was observed where df(υ)/dυ was positive, just below the auroral beam velocity. The measurement is shown to be consistent with instabilities driven by both Landau and cyclotron resonant interactions with upper hybrid waves, and also with the earlier observation of modulations at 2.65 MHz ( ≈ fuh) seen on a low altitude rocket E2-B (apogee 230 km).