Velocity Oscillations in the Chromosphere and the Transition Region above Plage Regions

• Kwak, Hannah (Astronomy Program, Department of Physics & Astronomy, Seoul National University) ;
• Chae, Jongchul (Astronomy Program, Department of Physics & Astronomy, Seoul National University)
• Published : 2017.10.10

Abstract

We investigate velocity oscillations in the active region plage by using the high-spatial, high-spectral and high-temporal resolution spectral data acquired by the Interface Region Imaging Spectrograph (IRIS). From the Mn I $2801.907{\AA}$ (lower chromosphere), C II (lower transition region) and Si IV (middle transition region) lines, we measure the line of sight Doppler velocity at different atmospheric layers, and present results of wavelet analysis of the plage region with a range of periods from 2 to 8 minutes. In addition, we present correlations of the oscillations from the lower chromosphere to the middle transition region. Finally, we will discuss the regional dependence of the oscillation properties on physical properties such as temperature and magnetic field inclination.