Analysis of the Quasi-Periodic Pulsations in the X9.3 and X8.3 Flares on 6 and 10 September 2017 Observed by SDO/EVE, PROBA2/LYRA and MAVEN/EUVM
Abstract
Quasi-periodic pulsations (QPPs) refer to nearly-periodic oscillations that are often observed in irradiance time series during most solar flares and have also been reported in several stellar flares. Two families of mechanisms are usually invoked to explain QPPs: MHD waves and quasi-periodic particle acceleration. In both cases, QPPs could inform us on the conditions in which flares happen. The two strongest flares of the current solar cycle, i.e. the X9.3 flare on 6 September 2017 and the off-limb X8.3 flare that occurred four days later, have been observed by two SXR-to-UV radiometers: SDO/EVE and PROBA2/LYRA. These two flares were produced in similar conditions by the same active region. However, if QPPs with periods between 1 and 100 s were clearly detected in the LYRA and EVE time series during the first event, this was not the case during the second event. To understand what causes this difference between the two flares, we involve the observations by a third instrument: MAVEN/EUVM orbiting Mars. We will compare the observations by the three instruments and see how this can shed some light on the QPP phenomenon.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMSH13D3422D
- Keywords:
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- 7519 Flares;
- SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY;
- 7554 X-rays;
- gamma rays;
- and neutrinos;
- SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY;
- 7845 Particle acceleration;
- SPACE PLASMA PHYSICS;
- 7974 Solar effects;
- SPACE WEATHER