| Presentation Title: | Investigating Coronal Bright Points: Statistical Analysis and 3D MHD Simulation with Hinode and SDO |
| Author(s): | Isabella Kraus & Philippe-A. Bourdin |
Abstract:
Understanding the precise mechanism behind coronal heating remains a fundamental challenge in solar physics. Smaller-scale bipolar regions, extending up to 10 Mm, show extreme UV emission in the form of coronal bright points (CBPs). In this study, we show a comprehensive analysis of CBPs using continous data from the Solar Dynamics Observatory (SDO) spacecraft to track their lifetimes. Our investigation aims to validate the co-rotation of the lower corona with the photosphere through CBP tracking data. For the statistics we use 346 CBPs and analyze their lifetime, shape, polarity, merging behavior, flux emergence, and magnetic evolution. 80% of CBPs magnetic field approach during their lifetime, merge, and annihilate in the end of their lifecycle. Then we see in all AIA channels how the CBPs are fading out and finally disappear. The analysis demonstrates that most of the CBPs have mixed polarities. The hottest and brightest ones show bipolar structure and a significantly longer lifetime. Only one-third of the CBP show a merging behavior with another CBP. Our findings reveal that loop-like CBPs mostly originate from bipolar regions, with weaker magnetic polarities giving rise to fainter and cooler CBPs. Additionally, we observe that typical CPBs with lifetimes exceed 6 hours, supporting the hypothesis that CBP heating primarily stems from magnetic energy dissipation via a relatively steady and gradual magnetic reconnection process. Moreover, we aim to replicate an isolated CBP in a 3D MHD simulation. To achieve this, we rely on observational data from both SDO/HMI and Hinode/NFI instruments. As a result of different FOV and resolutions of SDO’s and Hinode’s instruments, combining their data requires careful alignment to maintain consistency in the simulated photospheric magnetic fields. To achieve this, we use a sophisticated multi-scale overlaying technique to enhance the Hinode observations with SDO data, enabling the creation of adequate input for the MHD simulation. In our simulation setup, the bottom and top boundaries are treated as fully closed to mass and heat flows. The ensuing simulation output enables the computation of synthetic UV emission maps, which can be directly compared to observations from SDO and Hinode. With our model, we will be able to distinguish different heating mechanisms that act in the corona. This allows us to tell if the heating of CBPs is substantially different from the one in coronal loops above active regions.