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.
During a substorm on 27 January 2004, energetic particle injections associated with ULF waves have been detected by Cluster satellites. The observed ULF waves with the period of 1 minutes are probably the third harmonic mode, which can simultaneously interact with both substorm injected "hot" particles from the magnetotail and cold outflow ions from the Earth's ionosphere.
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. 