The Application of the Filtered Backprojection Algorithm to Solar Rotational Tomography
| Autor: | Ryun-Young Kwon, Jongchul Chae, Kyuhyoun Cho, Su-Chan Bong, Kyung-Suk Cho |
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| Rok vydání: | 2020 |
| Předmět: |
Physics
Electron density 010504 meteorology & atmospheric sciences Extreme ultraviolet lithography Coronal hole Inverse transform sampling FOS: Physical sciences Astronomy and Astrophysics 01 natural sciences Corona law.invention Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science law Extreme ultraviolet 0103 physical sciences Physics::Space Physics Astrophysics::Solar and Stellar Astrophysics Tomography 010303 astronomy & astrophysics Coronagraph Algorithm Solar and Stellar Astrophysics (astro-ph.SR) 0105 earth and related environmental sciences |
| DOI: | 10.48550/arxiv.2005.06388 |
| Popis: | Solar rotational tomography (SRT) is an important method to reconstruct the physical parameters of the three-dimensional solar corona. Here we propose an approach to apply the filtered backprojection (FBP) algorithm to the SRT. The FBP algorithm is generally not suitable for SRT due to the several issues with solar extreme ultraviolet (EUV) observations, in particular a problem caused by missing data because of the unobserved back side of corona hidden behind the Sun. We developed a method to generate a modified sinogram which resolves the blocking problem. The modified sinogram is generated by combining the EUV data at two opposite sites observed by the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). We generated the modified sinogram for about one month in 2019 February and reconstructed the three-dimensional corona under the static state assumption. In order to obtain the physical parameters of the corona, we employed a DEM inversion method. We tested the performance of the FBP algorithm with the modified sinogram by comparing the reconstructed data with the observed EUV image, electron density models, previous studies of electron temperature, and an observed coronagraph image. The results illustrate that the FBP algorithm reasonably reconstructs the bright regions and the coronal holes, and can reproduce their physical parameters. The main advantage of the FBP algorithm is that it is easy to understand and computationally efficient. Thus, it enables us to easily probe the inhomogeneous coronal electron density and temperature distribution of the solar corona. Comment: Accepted for ApJ |
| Databáze: | OpenAIRE |
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