A cancellation nanoflare model for solar chromospheric and coronal heating. III. 3D simulations and atmospheric response
MetadataShow full item record
Inspired by recent observations suggesting that photospheric magnetic flux cancellation occurs much more frequently than previously thought, we analytically estimated the energy released from reconnection driven by photospheric flux cancellation, and propose that it can act as a mechanism for chromospheric and coronal heating. Using two-dimensional simulations we validated the analytical estimates and studied the resulting atmospheric response. In the present work, we set up 3D resistive MHD simulations of two canceling polarities in a stratified atmosphere with a horizontal external field to further validate and improve upon the analytical estimates. The computational evaluation of the parameters associated with the energy release are in good qualitative agreement with the analytical estimates. The computational Poynting energy flux into the current sheet is in good qualitative agreement with the analytical estimates, after correcting the analytical expression to better account for the horizontal extent of the current sheet. The atmospheric response to the cancellation is the formation of hot ejections, cool ejections, or a combination of both hot and cool ejections, which can appear with a time difference and/or be spatially offset, depending on the properties of the canceling region and the resulting height of the reconnection. Therefore, during the cancellation, a wide spectrum of ejections can be formed, which can account for the variety of multi-thermal ejections associated with Ellerman bombs, UV bursts, and IRIS bombs, and also other ejections associated with small-scale canceling regions and spicules.
Syntelis , P & Priest , E R 2020 , ' A cancellation nanoflare model for solar chromospheric and coronal heating. III. 3D simulations and atmospheric response ' , Astrophysical Journal , vol. 891 , no. 1 , 52 . https://doi.org/10.3847/1538-4357/ab6ffc
Copyright © 2020. The American Astronomical Society. All rights reserved. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the final published version of the work, which was originally published at https://doi.org/10.3847/1538-4357/ab6ffc
DescriptionThis research has made use of NASA's Astrophysics Data System. This work was supported by computational time granted from the Greek Research and Technology Network (GRNET) in the National HPC facility ARIS. P.S. acknowledges support by the ERC synergy grant "The Whole Sun."
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
Showing items related by title, author, creator and subject.
Platten, S.J.; Parnell, C.E.; Haynes, A.L.; Priest, E.R.; MacKay, D.H. (2014-05-01) - Journal articleContext. The complicated distribution of magnetic flux across the solar photosphere results in a complex web of coronal magnetic field structures. To understand this complexity, the magnetic skeleton of the coronal field ...
Bramich, Daniel Martyn (University of St Andrews, 2005) - ThesisWe present results from 30 nights of observations of the intermediate-age Solar-metallicity open cluster NGC 7789 with the WFC camera on the INT telescope in La Palma. From ~900 epochs, we obtained lightcurves and Sloan ...
Johnston, Alan (University of St Andrews, 1994) - ThesisA study has been made of the global solar oscillations known as p-modes. The Sun is represented by a plane-parallel stratified plasma. Solutions are found to the magnetohydrodynamic equations of motion in such a plasma, ...