Conveners
Poster Session 7.5
- Alessandro Bemporad (Istituto Nazionale di Astrofisica (INAF))
On 21 February and 21-22 March 2021, the Extreme Ultraviolet Imager (EUI) onboard Solar Orbiter (SolO) observed three prominence eruptions. The eruptions were associated with coronal mass ejections (CMEs) observed by Metis, SolO's coronagraph. All three eruptions were also observed by instruments onboard PROBA2, SDO, STEREO-A and SOHO. An analysis of these eruptions is performed, together with...
Like their larger counterparts, solar microflares release magnetic energy and accelerate particles to relativistic speeds. Even though they are generally shorter and often more compact than larger flares, they can display a surprising complexity and provide new insights into where and when particles are accelerated. Signatures of accelerated electrons are most readily observed at X-ray and...
MHD plasma turbulence is believed to play a vital role in the production of energetic electrons during solar flares and non-thermal broadening of spectral lines is a key sign of this turbulence. Here, we determine how flare turbulence evolves in time and in space using spectral profiles of Fe xxiv, Fe xxiii and Fe xvi, observed by Hinode/EIS. Maps of non-thermal velocity are created for times...
Prediction of the future flare productivity of an active region (AR) when it is in the early-emergence stage is a longstanding problem. The aim of this study is to probe two parameters of the photospheric magnetic field, both derived during the emergence phase of an AR, and to compare them with the flare productivity of a well developed AR. The parameters are: (i) the index of the magnetic...
The Spectrometer/Telescope for Imaging X-rays (STIX) is a remote sensing instrument on-board the Solar Orbiter mission, conceived for the measurement of hard X-ray photons emitted by thermal and non-thermal mechanisms during solar flares. In particular, the scientific goal of STIX is to provide information on location, timing and spectrum of the accelerated electrons at the Sun. The STIX...
Two strong homologous white-light flares of GOES X-class occurred on the Sun on September 06, 2017. We describe the peculiarity of these events occurred in the super active region NOAA 12673, with a time interval, between their peaks, of about 3 hr. Using photospheric vector magnetograms, taken before the beginning of the two X-class events, as boundary conditions to reconstruct the...
The study of the localized plasma conditions before the impulsive phase of a solar flare can help us understand the physical processes that occur leading up to the main flare energy release. Here, we present evidence of a hot X-ray ‘onset’ interval of enhanced isothermal plasma temperatures in the range of 10-15 MK up to tens of seconds prior to the flare’s impulsive phase. This ‘hot onset’...
