Skip to main content
SearchLogin or Signup

Multi-spacecraft Observation of Coronal loops to Verify Loop Reconstruction and Infer Cross Sections

Published onAug 18, 2020
Multi-spacecraft Observation of Coronal loops to Verify Loop Reconstruction and Infer Cross Sections

The corona of an active region is believed to be a low-beta plasma in which a subset of field lines are energized and appear as coronal loops in soft X-ray and EUV images. Malanushenko et al. (2009) proposed a method, alpha-h-fitting, of using these loops, along with a line-of-sight photospheric magnetogram, to infer the non-linear force free field of the corona and the three-dimensional shape of each loop. McCarthy et al. (2019) observed an active region pair (NOAA AR11149/11147) over 48 hours and used the alpha-h-fitting method on 199 of the loops interconnecting the pair observed in SDO/AIA 171A. They used these to compute the total magnetic flux interconnecting the regions under the assumption that each loop had a circular cross section. The fitting and the assumption of circular cross-sections can both be tested using observations of these regions from multiple vantage points provided by the STEREO/EUVI images. This observation occurred at a fortunate time since both STEREO spacecraft are nearly in quadrature with AIA and from the twin spacecraft the loops from the McCarthy et al. (2019) are viewed above the limb from both vantage points. Here, we use the multiple viewing angles to confirm the three-dimensional reconstruction. We are also able to use the reconstruction to unambiguously map a point as viewed from AIA to the corresponding location in the image taken with EUVI, and then the measured diameters of that flux tube from these multiple vantage points.


Comments
0
comment

No comments here