Energetic electron response to interplanetary shocks at geosynchronous orbit


We study the response of energetic electrons at geosynchronous orbit to interplanetary shocks, to show the increase of low-energy electron fluxes after the shock arrival. However, in higher energy channels fluxes show smaller increases and eventually become unchanged or even decrease. Statistical analysis also reveals a frequency preference for 2.2 mHz and 3.3 mHz oscillations of energetic electron fluxes, with different phase and power distributions for high- and low-energy electron fluxes.

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Evidence of Landau and cyclotron resonance between protons and kinetic waves


They are two closely connected science questions about how the solar wind is heated and how the turbulence is dissipated. The research breakthrough is blocked by the difficulty of combining the wave diagnosis and particle kinetics analysis together. We provided the simultaneous information of wave features and particle kinetics. We confirmed again the two components of waves at ion kinetic scales, quasi-parallel ion cyclotron waves and quasi-perpendicular kinetic Alfven waves. We identified the evidence of multiple resonance plateaus: left-cyclotron resonance between ion cyclotron waves and proton core components, right-cyclotron resonance and Landau resonance between kinetic Alfven waves and proton beam components. Hence, a scenario of solar wind proton joint heating perpendicularly and parallely by the two-component kinetic waves is suggested.

This work is published on Astrophys. J. Lett. (ApJL)上 (He, J.-S., et al., ApJL, 800, L31, 2015)。
Authors: Jiansen HE, Linghua WANG, Chuanyi TU, Eckart MARSCH, Qiugang ZONG

This work is supported by NSFC innovation group program, key program, excellent scholarship program, and general program.

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Simulation of fast-mode magneto sonic waves excited by plasmid ejections


The phenomena of fast magnetosonic waves propagation in the solar corona has recently been observed with SDO/AIA observatory. The underlying physical mechanism remains unclear. We proposed a idea that the fast magnetosonic waves may be excited by the impact of reconnection jet flow into the ambient coronal open fields. We carried out the numerical simulation to reproduce this scenario self-consistently. In the numerical process, coronal closed loops are driven by the shear motions in the photoshere, give rise to magnetic reconnection with open fields in the neighborhood, eject high-speed plasmoids. The ejected high-speed plasmoids finally impact into the upflow region, and thereby exciting the fast magnetosonic waves, which are similar to the observations in many characteristics.

This work is published on ApJ

Authors: Liping YANG, Lei ZHANG, Jiansen HE, Hardi PETER, Chuanyi TU, Linghua WANG, Shaohua ZHANG, and Xueshang FENG.

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