Lightning-generated whistler(LGW)is an important electromagnetic wave in the magnetosphere,causing energetic electron losses.Here we analyze the LGW distribution and propagation using Van Allen Probes data and ray-tra...Lightning-generated whistler(LGW)is an important electromagnetic wave in the magnetosphere,causing energetic electron losses.Here we analyze the LGW distribution and propagation using Van Allen Probes data and ray-tracing simulation.The statistics show that LGW occurs more frequently at L<2.5 with higher amplitudes in the northern hemisphere.The Poynting flux demonstrates that LGW originates from both hemispheres within L~2.5,and propagates into the space as the wave power decays.The wave normal angle distributions indicate that LGW propagates quasi-parallel to the field line near its source and becomes oblique as the magnetic latitude decreases.Furthermore,we use the ray-tracing model to simulate the LGW propagation,and statistically analyze the propagation characteristics of LGW,which are consistent with the observational data.This paper presents the latitudinal distribution and propagation properties of LGW based on statistics for the first time,providing new insights into the LGW generation and evolution in the magnetosphere.展开更多
Lightning-generated whistler(LGW) waves which induce energetic electron precipitation provide an important coupling between the ionosphere and radiation belts. Using the ray-tracing technique, we examine the propagati...Lightning-generated whistler(LGW) waves which induce energetic electron precipitation provide an important coupling between the ionosphere and radiation belts. Using the ray-tracing technique, we examine the propagation behaviour of LGW waves and show that they can travel upward into the radiation belts during higher geomagnetic activities due to the plasmapause inward compression, particularly in cases of lower wave frequencies, lower wave normal angles and azimuthal angles. Both perpendicular and parallel group velocities of LGW waves remain in relatively small values inside the plasmasphere but change rapidly to high values outside the plasmasphere. The launching latitude increases with increasing LGW wave normal angle. These results here further reveal a detailed picture on how LGW waves escape out of the plasmasphere and onto the radiation belts.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.42422406,42174185,42474209)the Science and Technology Development Fund,Macao SAR(Grant Nos.0042/2024/RIA1,0176/2023/RIA3,0008/2024/AKP and 002/2024/SKL)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2024A1515012093)。
文摘Lightning-generated whistler(LGW)is an important electromagnetic wave in the magnetosphere,causing energetic electron losses.Here we analyze the LGW distribution and propagation using Van Allen Probes data and ray-tracing simulation.The statistics show that LGW occurs more frequently at L<2.5 with higher amplitudes in the northern hemisphere.The Poynting flux demonstrates that LGW originates from both hemispheres within L~2.5,and propagates into the space as the wave power decays.The wave normal angle distributions indicate that LGW propagates quasi-parallel to the field line near its source and becomes oblique as the magnetic latitude decreases.Furthermore,we use the ray-tracing model to simulate the LGW propagation,and statistically analyze the propagation characteristics of LGW,which are consistent with the observational data.This paper presents the latitudinal distribution and propagation properties of LGW based on statistics for the first time,providing new insights into the LGW generation and evolution in the magnetosphere.
基金supported by the National Natural Science Foundation of China(Grant Nos.41531072,41674166,41774194&41804171)。
文摘Lightning-generated whistler(LGW) waves which induce energetic electron precipitation provide an important coupling between the ionosphere and radiation belts. Using the ray-tracing technique, we examine the propagation behaviour of LGW waves and show that they can travel upward into the radiation belts during higher geomagnetic activities due to the plasmapause inward compression, particularly in cases of lower wave frequencies, lower wave normal angles and azimuthal angles. Both perpendicular and parallel group velocities of LGW waves remain in relatively small values inside the plasmasphere but change rapidly to high values outside the plasmasphere. The launching latitude increases with increasing LGW wave normal angle. These results here further reveal a detailed picture on how LGW waves escape out of the plasmasphere and onto the radiation belts.
