Search Publications
Observation of super-Alfvénic slippage of reconnecting magnetic field lines on the Sun
Polito, Vanessa; De Pontieu, Bart; Aulanier, Guillaume +3 more
Slipping motions of magnetic field lines are a distinct signature of three-dimensional magnetic reconnection, a fundamental process driving solar and stellar flares. While being a key prediction of numerical experiments, the rapid super-Alfvénic field line slippage driven by the `slip-running' reconnection has remained elusive in previous observat…
Chromospheric and coronal heating in an active region plage by dissipation of currents from braiding
De Pontieu, Bart; Hansteen, Viggo; Sainz Dalda, Alberto +3 more
The question of what heats the outer solar atmosphere remains one of the longstanding mysteries in astrophysics. Statistical studies of Sun-like stars reveal a correlation between global chromospheric and coronal emissions, constraining theoretical models of potential heating mechanisms. However, spatially resolved observations of the Sun have sur…
Complete replacement of magnetic flux in a flux rope during a coronal mass ejection
Veronig, Astrid M.; Li, Ting; Wang, Yuming +5 more
Solar coronal mass ejections are the most energetic events in the Solar System. In their standard formation model, a magnetic flux rope builds up into a coronal mass ejection through magnetic reconnection that continually converts overlying, untwisted magnetic flux into twisted flux enveloping the pre-existing rope. However, only a minority of cor…
Reconnection nanojets in the solar corona
Antolin, Patrick; Pagano, Paolo; Testa, Paola +2 more
The solar corona is shaped and mysteriously heated to millions of degrees by the Sun's magnetic field. It has long been hypothesized that the heating results from a myriad of tiny magnetic energy outbursts called nanoflares, driven by the fundamental process of magnetic reconnection. Misaligned magnetic field lines can break and reconnect, produci…
The origin of reconnection-mediated transient brightenings in the solar transition region
Winebarger, Amy R.; Bahauddin, Shah Mohammad; Bradshaw, Stephen J.
The ultraviolet emission from the solar transition region is dominated by dynamic, low-lying magnetic loops. The enhanced spatial and temporal resolution of the solar observation satellite Interface Region Imaging Spectrograph (IRIS) has made it possible to study these structures in fine detail. IRIS has observed `transient brightenings' in these …
A comprehensive three-dimensional radiative magnetohydrodynamic simulation of a solar flare
Cheung, M. C. M.; De Pontieu, B.; Sainz Dalda, A. +11 more
Solar and stellar flares are the most intense emitters of X-rays and extreme ultraviolet radiation in planetary systems1,2. On the Sun, strong flares are usually found in newly emerging sunspot regions3. The emergence of these magnetic sunspot groups leads to the accumulation of magnetic energy in the corona. When the magneti…
Confined pseudo-shocks as an energy source for the active solar corona
Stangalini, Marco; Kayshap, Pradeep; Dwivedi, Bhola N. +7 more
The Sun's active corona requires an energy flux of 103 W m-2 to compensate for radiative losses and to maintain its high temperature1. Plasma moves in the corona through magnetic loops2,3, which may be connected with the flows in and around sunspots4-6. Global energizing processes (for example…