On the Constraints and Observational Manifestations of Failed Solar Eruptions in Toroidal Magnetic Cage

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Guo, Jinhan, Guo, Y., Wu, H., Schmieder, B., Démoulin, P., Ni, Y. W., Wang, C., Poedts, S., Li, T., Wang, Wensi, Zhou, Y. H., Chen, P. F.
Formato: Preprint
Publicado: 2026
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866910065650302976
author Guo, Jinhan
Guo, Y.
Wu, H.
Schmieder, B.
Démoulin, P.
Ni, Y. W.
Wang, C.
Poedts, S.
Li, T.
Wang, Wensi
Zhou, Y. H.
Chen, P. F.
author_facet Guo, Jinhan
Guo, Y.
Wu, H.
Schmieder, B.
Démoulin, P.
Ni, Y. W.
Wang, C.
Poedts, S.
Li, T.
Wang, Wensi
Zhou, Y. H.
Chen, P. F.
contents Observations show that many solar eruptions remain confined within strong overlying magnetic fields, forming a so-called magnetic cage. While confinement by poloidal overlying fields has been widely investigated, the role of strong external toroidal fields remains unclear. Using three-dimensional magnetohydrodynamic simulations, we study confined eruptions in a toroidal magnetic cage, focusing on the interplay between the Lorentz force and magnetic reconnection, and their observational signatures. We further employ a guiding-center test-particle approach to synthesize hard X-ray emission for comparison between thermal and nonthermal responses. We find that overlying toroidal fields play a crucial role in confinement by generating strong return currents that produce a significant downward Lorentz force, suppressing flux rope ascent. At the same time, they induce large-angle rotation of the flux rope, leading to reconnection with overlying fields and eventual break-up. Synthetic EUV emission reveals multi-ribbon flares with highly sheared, globally cowboy-hat-like loop structures. Hard X-ray diagnostics show that thermal and nonthermal emissions are not co-spatial, with return currents acting as an efficient accelerator of energetic electrons. These results demonstrate that toroidal-field-induced forces govern both the confinement and rotation of erupting flux ropes, providing an explanation for failed eruptions even under torus-unstable conditions. These results suggest that the morphology and shearing angle of flare loops are the useful diagnostics for distinguishing confined from eruptive events.
format Preprint
id arxiv_https___arxiv_org_abs_2603_21885
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle On the Constraints and Observational Manifestations of Failed Solar Eruptions in Toroidal Magnetic Cage
Guo, Jinhan
Guo, Y.
Wu, H.
Schmieder, B.
Démoulin, P.
Ni, Y. W.
Wang, C.
Poedts, S.
Li, T.
Wang, Wensi
Zhou, Y. H.
Chen, P. F.
Solar and Stellar Astrophysics
Observations show that many solar eruptions remain confined within strong overlying magnetic fields, forming a so-called magnetic cage. While confinement by poloidal overlying fields has been widely investigated, the role of strong external toroidal fields remains unclear. Using three-dimensional magnetohydrodynamic simulations, we study confined eruptions in a toroidal magnetic cage, focusing on the interplay between the Lorentz force and magnetic reconnection, and their observational signatures. We further employ a guiding-center test-particle approach to synthesize hard X-ray emission for comparison between thermal and nonthermal responses. We find that overlying toroidal fields play a crucial role in confinement by generating strong return currents that produce a significant downward Lorentz force, suppressing flux rope ascent. At the same time, they induce large-angle rotation of the flux rope, leading to reconnection with overlying fields and eventual break-up. Synthetic EUV emission reveals multi-ribbon flares with highly sheared, globally cowboy-hat-like loop structures. Hard X-ray diagnostics show that thermal and nonthermal emissions are not co-spatial, with return currents acting as an efficient accelerator of energetic electrons. These results demonstrate that toroidal-field-induced forces govern both the confinement and rotation of erupting flux ropes, providing an explanation for failed eruptions even under torus-unstable conditions. These results suggest that the morphology and shearing angle of flare loops are the useful diagnostics for distinguishing confined from eruptive events.
title On the Constraints and Observational Manifestations of Failed Solar Eruptions in Toroidal Magnetic Cage
topic Solar and Stellar Astrophysics
url https://arxiv.org/abs/2603.21885