摘要
In this study,we present three experiments carried out at the EISCAT(European Incoherent Scatter Scientific Association)heating facility on October 29 and 30,2015.The results from the first experiment showed overshoot during the O-mode heating period.The second experiment,which used cold-start X-mode heating,showed the generation of parametric decay instability,whereas overshoot was not observed.The third experiment used power-stepped X-mode heating with noticeable O-mode wave leakage.Parametric decay instability and oscillating two-stream instability were generated at the O-mode reflection height without the overshoot effect,which implies suppression of the thermal parametric instability with X-mode heating.We propose that the electron temperature increased because X-mode heating below the upper hybrid height decreased the growth rate of the thermal parametric instability.
基金
EISCAT is an international scientific association supported by research organizations in China(China Research Institute of Radiowave Propagation(CRIRP)),Finland(Suomen Akatemia(SA)),Japan(National Institute of Polar Research(NIPR)and Solar-Terrestrial Environment Laboratory(STEL)),Norway(The Research Council of Norway(NFR)),Sweden(Swedish Research Council(VR)),and the United Kingdom(Natural Environment Research Council(NERC)).This work was supported by the National Natural Science Foundation of China(NSFC,grants 41204111,41574146,41774162,and 41704155)
the China Postdoctoral Science Foundation(grant 2017M622504).The experiment described in this work was carried out by the Russian team led by N.F.Blagoveshchenskaya.The data used in this research are available through the EISCAT Madrigal database(http://www.eiscat.se/madrigal/)and EISCAT Dynasonde database(https://dynserv.eiscat.uit.no/).
