Case study of ion line spectra during modulated PMSE condition

Based on observations of EISCAT VHF radar, this study presents the analysis of ion line spectra within PMSE altitude (80-90 km) during heating experiment on 13 July 2007. The results show that the strength of ion lines during the heating moment is smaller as compared to its strength during unheated moments. In PMSE altitude no double humped spectra of ion line is observed during the heating moment, which is the general characteristic of ion line spectra above PMSE altitude. The intensity of ion line shows variations with altitude and time. During heating moment, the asymmetrical peaks of ion line can be discussed.