Title: The First Imaging of Hard X-ray Emission from Solar-flare-accelerated Electrons on Timescales Relevant to the Acceleration Process
Speaker: Danny Ryan, Mullard Space Science Laboratory
Non-thermal electron acceleration is one of the earliest observable signatures of magnetic reconnection in solar flares and eruptions, and is key to understanding how it triggers and drives such events. In recent decades, modelling, as well as spatially integrated hard X-ray (HXR) observations, suggest that this process occurs on timescales less than or equal to 1s. However, further probing the acceleration process requires characterising the spatial and spectral evolution of the electrons with HXR imaging spectroscopy. Yet, this has not previously been available on such fast timescales.
In this talk, we discuss the first 1-s HXR spectroscopic imaging of non-thermal flare-accelerated electrons. Thanks to Solar Orbiter/STIX observations of one of the most intense solar flares ever observed (SOL2024-05-20T05:14L171C109, estimated at X16.5 class), we find physical changes in the non-thermal HXR source morphologies on timescales at least as fast as 1 second. This is despite slower evolution of the spatially integrated HXR spectrum. This highlights the importance of high spatial resolution sub-second HXR imaging spectroscopy for elucidating non-thermal electron acceleration, and how it drives and sustains solar flares and eruptions.
Where: Meridian Room, ROB or online (https://observatory.webex.com/observatory/j.php?MTID=maed180db988b21669f4ba8df631cebc2)
When: Thursday October 15 at 14h30
Contact: Cis Verbeeck (ROB)
