Quasi-periodic oscillations in flare emission in the solar chromosphere simultaneously observed with IRIS and SDO
Abstract
Quasi-periodic pulsations (QPPs) appear in the emission spectrum of most solar flares over all wavelength bands and, in some cases, multiple periodicities. There is some ambiguity as to the type of emission in which they occur (i.e. line or continuum), and the mechanism that drives them. Current possibilities include magnetohydrodynamic oscillations and plasma flows of non-thermal electrons after the magnetic reconnection process. Here, we investigate the response of the chromosphere to solar flares by inspecting the power of the 3-minute oscillations before, during and after flares, in order to constrain both the start time of this power and where it originates. For this preliminary study, we present analysis of continuum images from the Helioseismic and Magnetic Imager (HMI) and of 1600 and 1700 Angstrom UV images from the Atmospheric Imaging Assembly (AIA), two of the instruments on board the Solar Dynamics Observatory (SDO), of the 2011 February 15 X-class flare. Future work will involve the Interface Region Imaging Spectrometer (IRIS) to show whether the oscillations are manifest in the line or continuum emission, a distinction that can be lost in integrated bandpass intensity images. Results from wavelet analysis and Fourier transforms will be explored.
- Publication:
-
Solar Heliospheric and INterplanetary Environment (SHINE 2017)
- Pub Date:
- July 2017
- Bibcode:
- 2017shin.confE.164F