Related papers: Dynamics of the Transition corona
We aim to reproduce the structure of the corona above a solar active region as seen in the extreme ultraviolet (EUV) using a three-dimensional magnetohydrodynamic (3D MHD) model. The 3D MHD data-driven model solves the induction equation…
We present a new global model of the solar corona, including the low corona, the transition region and the top of chromosphere. The realistic 3D magnetic field is simulated using the data from the photospheric magnetic field measurements.…
We present numerical models from the field-aligned Hydrodynamics and Radiation Code (HYDRAD) of a highly asymmetric closed coronal loop with near-singular expansion factor. This loop was chosen to simulate a coronal magnetic flux tube that…
Magnetic reconnection is a well-accepted part of the theory of solar eruptive events, though the evidence is still circumstantial. Intrinsic to the reconnection picture of a solar eruptive event, particularly in the standard model for…
Perhaps the most compelling evidence for the role of magnetic reconnection in solar flares comes from the supra-arcade downflows that have been observed above many post-flare loop arcades. These downflows are thought to be related to highly…
Increasing evidence for coronal heating contributions from cooler solar atmospheric layers, notably quiet Sun (QS) conditions, challenges standard solar atmospheric descriptions of bright transition region (TR) emission. As such, questions…
Vortex motions are frequently observed on the solar photosphere. These motions may play a key role in the transport of energy and momentum from the lower atmosphere into the upper solar atmosphere, contributing to coronal heating. The lower…
Magnetic reconnection is a process that changes magnetic field topology in highly conducting fluids. Traditionally, magnetic reconnection was associated mostly with solar flares. In reality, the process must be ubiquitous as astrophysical…
A system of multiple open magnetic flux tubes spanning the solar photosphere and lower corona is modelled analytically, within a realistic stratified atmosphere subject to solar gravity. This extends results for a single magnetic flux tube…
Context. In the upper atmosphere of the Sun observations show convincing evidence for crossing and twisted structures, which are interpreted as mutual helicity and self-helicity. Aims. We use observations with the new Interface Region…
The magnetic topology and field line random walk properties of a nanoflare-heated and magnetically confined corona are investigated in the reduced magnetohydrodynamic regime. Field lines originating from current sheets form coherent…
We report multi-wavelength ultraviolet observations taken with the IRIS satellite, concerning the emergence phase in the upper chromosphere and transition region of an emerging flux region (EFR) embedded in the pre-existing field of active…
The response of the solar coronal magnetic field to small-scale photospheric boundary motions including the possible formation of current sheets via the Parker scenario is one of open questions of solar physics. Here we address the problem…
Partially-ionized plasmas consist of charged and neutral particles whose mutual collisions modify magnetic reconnection compared with the fully-ionized case. The collisions alter the rate and locations of the magnetic dissipation heating…
Recent observations suggest that magnetic flux cancellation may play a crucial role in heating the Sun's upper atmosphere (chromosphere, transition region, corona). Here, we intended to validate an analytic model for magnetic reconnection…
Current models of the solar wind must approximate (or ignore) the small-scale dynamics within the solar atmosphere, however these are likely important in shaping the emerging wave-turbulence spectrum and ultimately heating/accelerating the…
Three-dimensional null points are present in abundance in the solar corona, and the same is likely to be true in other astrophysical environments. Recent studies suggest that reconnection at such 3D nulls may play an important role in the…
The dynamics of magnetic fields in closed regions of solar and stellar coronae are investigated with a reduced magnetohydrodynamic (MHD) model in the framework of Parker scenario for coronal heating. A novel analysis of reduced MHD…
The present work is on the study of a coronal streamer observed in March 2008 at high spectral and spatial resolution by the Ultraviolet Coronagraph Spectrometer (UVCS) onboard SOHO. On the basis of a spectroscopic analysis of the O VI…
Combined tearing-thermal evolution plays an important role in the disruption of current sheets, and formation of cool condensations within the solar atmosphere. However, this has received limited attention to date. We numerically explore a…