Speaker
Description
First Name: Paolo
Last Name: Massa
Affiliation: University of Applied Sciences and Arts Northwestern Switzerland (FHNW)
All Authors: Paolo Massa, Alessia Guidetti, Muriel Zoë Stiefel, Säm Krucker
Abstract: The Spectrometer/Telescope for Imaging X-rays (STIX) on board the ESA Solar Orbiter mission provides imaging and spectroscopic information on the X-ray radiation from solar flares. STIX contains pairs of tungsten grids which transmit the incident X-ray radiation and create Moire patterns on the surface of Cadmium Telluride detectors. The contrast (amplitude) and the location of the fringes (phase) of the patterns is related to amplitude and phase of spatial Fourier components of the X-ray sources. Therefore, the image of the flaring sources can be retrieved by solving an inverse imaging problem from Fourier data. In this presentation, we describe a new technique that allows imaging of the spatial distribution of the Emission Measure (EM) of plasma populations at different temperatures from STIX data. An a priori spectral analysis determines the number and the temperature of the different isothermal populations, and these results are utilized within the reconstruction process to obtain EM images for each temperature. We show applications of our technique for the imaging of hot and superhot plasma populations in large solar flares. Finally, we discuss similarities and differences between our methodology and the recently introduced Spectral Component Imaging technique.