| Name: | Raveena Khan |
| Affiliation: | Indian Institute of Astrophysics |
| Conference ID : | ASI2024_603 |
| Title : | FORWARD modelling of Ne VIII 770 Å line as a coronal magnetic field diagnostic |
| Authors : | Raveena Khan, Sarah Gibson, Roberto Casini, K. Nagaraju |
| Authors Affiliation: | Raveena Khan and K. Nagaraju Affiliation (Indian Institute of Astrophysics, Bengaluru 560034, India)
Sarah Gibson and Roberto Casini Affiliation (High Altitude Observatory, National Center for Atmospheric Research, Boulder, CO 80307, USA)
Raveena Khan Affiliation (University of Calcutta, College Street, Kolkata 700073, India)
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| Mode of Presentation: | Poster |
| Abstract Category : | Sun, Solar System, Exoplanets, and Astrobiology |
| Abstract : | The coronal magnetism is the primary driver of most of the solar events such as flares, coronal mass ejections (CMEs), and solar energetic particles. It is an important quantity to understand the fundamental plasma processes in the upper solar atmosphere, such as plasma heating, hydro-magnetic instabilities, and particle acceleration. Spectropolarimetry in the extreme-ultraviolet (EUV) is a promising technique for probing the magnetic fields in the solar corona both on the disk and off the limb of the Sun. However, the circular polarization signals (most commonly measured) due to Zeeman effect is very weak, of the order of 10^(-5) in EUV, for typical coronal field strengths of a few gauss. Therefore, we have computed the linear polarization of EUV resonance line radiation due to the magnetic Hanle effect, which refers to the modification of the scattering line polarization and rotation of the plane of polarization in the presence of an external magnetic field. We have utilized 3D 'magneto-hydrodynamics around a sphere' (MAS) models to study the variation of the polarization signal through the different phases of Solar Cycles 24 and 25. In this presentation, the FORWARD modelling of an EUV coronal emission line, i.e. Ne VIII 770 Å, will be discussed. The magnetic sensitivity of Ne VIII resonance line and analysis of its linear polarization, in the presence of magnetic field and collisions, will be briefly presented. |
