Advanced Ground-Based Observations of LF/MF/HF Radio Noise from Auroral Latitudes

美国国家科学基金会去年资助的拉贝尔研究证明，使用廉价的地面仪器，有可能在极光区探测到至少两种LF/MF/HF频率（0.05- 5.0 MHz）的无线电现象。 这些包括近两倍和三倍的电离层电子陀螺频率和宽带噪声增强的频谱零点附近的谐波的陀螺频率的窄带发射。 虽然这两种现象的模型已经提出，其原因是不确定的，因为是其发生的范围和时间变化。 我们建议对这些波现象进行更先进的测量，包括从一系列台站进行测量，其目标如下：（1）确定波的纬度和时间依赖性;（2）利用波数据和补充电离层探测仪、磁力计、riometer和全天空照相机数据，测试几种产生波的特定模型;和（3）探索将这些波观测与CANOPUS/ISTO仪器结合使用，作为极光电离层的地面诊断。 虽然无线电辐射只占极光总能量的一小部分，但它们可能为更高能量的过程提供重要线索，类似于太阳无线电辐射被用来推断日冕中发生的过程。 ***

9316126 LaBelle Research funded by NSF during the past year has proven that using inexpensive ground-based instrumentation, it is possible to detect at least two types of radio phenomena at LF/MF/HF frquencoes (0.05- 5.0 MHz) in the auroral zone. These include narrowband emissions near twice and three times the ionospheric electron gyrofrequency and broadband noise enhancements with nulls in the spectrum near harmonies of the gyrofrequency. Although models have been proposed for both these phenomena, their cause is undetermined, as are the range and time variation of their occurrence. We propose to make more advanced measurements of these wave phenomena, including measurements from a chain of stations, with the following objectives: (1) to determine the latitude and time dependence of the waves; (2) to test several specific models for their generation, using wave data and complementary ionosonde, magnetometer, riometer, and all-sky camera data; and (3) to explore the use of these wave observations in combination with CANOPUS/ISTO instrumentation as a ground-based diagnostic of the auroral ionosphere. Although radio emissions comprise a small fraction of the total energy of the Aurora, they may provide important clues to the more energetic processes, in analogy to the way in which solar radio emissions have been used to infer the processes taking place in the solar corona. ***