A Hot Cusp-Shaped Confined Solar Flare

Abstract

We analyze a confined flare that developed a hot cusp-like structure high in the corona (H ~ 66 Mm). A growing cusp-shaped flare arcade is a typical feature in the standard model of eruptive flares, caused by magnetic reconnection at progressively larger coronal heights. In contrast, we observe a static hot cusp during a confined flare. Despite an initial vertical temperature distribution similar to that in eruptive flares, we observe a distinctly different evolution during the late (decay) phase, in the form of prolonged hot emission. The distinct cusp shape, rooted at locations of non-thermal precursor activity, was likely caused by a magnetic field arcade that kinked near the top. Our observations indicate that the prolonged heating was a result of slow local reconnection and an increased thermal pressure near the kinked apexes due to continuous plasma upflows.

arXiv comment10 pages, 5 figures

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Cited by in corpus (4)

• Successive occurrences of quasi-circular ribbon flares in a fan-spine-like configuration involving hyperbolic flux tube
• The Kinematic Evolution of Erupting Structures in Confined Solar Flares
• A Solar Magnetic-fan Flaring Arch Heated by Non-thermal Particles and Hot Plasma from an X-ray Jet Eruption
• Flare Expansion to a Magnetic Rope Accompanied by Rare Radio Bursts