Stereoscopic observations reveal coherent morphology and evolution of solar coronal loops
arXiv:2411.16943 · doi:10.1051/0004-6361/202452339
Abstract
Coronal loops generally trace magnetic lines of force in the upper solar atmosphere. Understanding the loop morphology and its temporal evolution has implications for coronal heating models that rely on plasma heating due to reconnection at current sheets. Simultaneous observations of coronal loops from multiple vantage points are best suited for this purpose. Here, we report a stereoscopic analysis of coronal loops in an active region based on observations from the Extreme Ultraviolet Imager on board the Solar Orbiter Spacecraft and the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory. Our stereoscopic analysis reveals that coronal loops have nearly circular cross-sectional widths and that they exhibit temporally coherent intensity variations along their lengths on timescales of around 30\,minutes. Results suggest that coronal loops can be best represented as three-dimensional monolithic or coherent plasma bundles that outline magnetic field lines. Therefore, at least on the scales resolved by Solar Orbiter, it is unlikely that coronal loops are manifestations of emission from the randomly aligned wrinkles in two-dimensional plasma sheets along the line-of-sight as proposed in the `coronal veil' hypothesis.
References in corpus (19)
- The Solar Orbiter mission -- Science overview
- On Solving the Coronal Heating Problem
- Coronal heating by MHD waves
- An Ab Initio approach to Solar Coronal Loops
- Structure of solar coronal loops: from miniature to large-scale
- Evidence for Widespread Cooling in an Active Region Observed with the SDO Atmospheric Imaging Assembly
- The Magnetic Structure of Coronal Loops Observed by TRACE
- Cooling Active Region Loops Observed With SXT and TRACE
- Constant cross section of loops in the solar corona
- The Width Distribution of Loops and Strands in the Solar Corona -- Are we Hitting Rock Bottom ?
- Solar coronal heating from small-scale magnetic braids
- An MHD avalanche model of multi-threaded coronal loop
- The Coronal Veil
- The temporal evolution of coronal loops observed by GOES-SXI
- Are constant loop widths an artifact of the background and the spatial resolution?
- A solar coronal loop in a box: Energy generation and heating
- A simple model for the evolution of multi-stranded coronal loops
- On Anisotropy in Expansion of Magnetic Flux Tubes in the Solar Corona
- Coronal Loop Expansion Properties Explained Using Separators