Related papers: Coronal Loop Expansion Properties Explained Using …
Multiwavelength observations of the propagating disturbances (PDs), discovered by Atmospheric Imaging Assembly (AIA) onboard Solar Dynamics Observatory (SDO), are analyzed to determine its driving mechanism and physical nature. Two magnetic…
Here we report on the unique observation of flaring coronal loops at the solar limb using high resolution imaging spectropolarimetry from the Swedish 1-meter Solar Telescope. The vantage position, orientation and nature of the chromospheric…
Cool stars like our Sun are surrounded by a million degree hot outer atmosphere, the corona. Since more than 60 years the physical nature of the processes heating the corona to temperatures well in excess of those on the stellar surface…
Coronal heating through the explosive release of magnetic energy remains an open problem in solar physics. Recent hydrodynamical models attempt an investigation by placing swarms of 'nanoflares' at random sites and times in modeled…
The fan-spine magnetic topology is believed to be responsible for many curious features in solar explosive events. A spine field line links distinct flux domains, but direct observation of such feature has been rare. Here we report a unique…
In this study we report detailed observations of magnetic environment at four footpoints of two warm coronal loops observed on 5 May 2016 in NOAA AR 12542 (Loop I) and 17 Dec 2015 in NOAA AR 12470 (Loop II). These loops were connecting a…
Coronal loops are the basic structures of the solar transition region and corona. The understanding of physical mechanism behind the loop heating, plasma flows, and filling are still considered a major challenge in the solar physics. The…
Context: Transverse loop oscillations and loop contractions are commonly associated with solar flares, but the two types of motion have traditionally been regarded as separate phenomena. Aims: We present an observation of coronal loops…
Magnetic reconnection at the interface between coronal holes and loops, so-called interchange reconnection, can release the hotter, denser plasma from magnetically confined regions into the heliosphere, contributing to the formation of the…
We discuss the evolution of solar coronal element abundances over an active region lifetime. Magneto-convection drives the complexity of magnetic fields that emerge above the photosphere. This complexity is dissipated, together with that of…
Global magnetic field extrapolations are now revealing the huge complexity of the Sun's corona, and in particular the structure of the boundary between open and closed magnetic flux. Moreover, recent developments indicate that magnetic…
We use a combination of analytical theory, numerical simulation, and data analysis to study the propagation of acoustic waves along coronal loops. We show that the intensity perturbation of a wave depends on a number of factors, including…
What physical mechanisms heat the outer solar or stellar atmosphere to million-Kelvin temperatures is a fundamental but long-standing open question. In particular, the solar corona in active region cores contains an even hotter component…
Magnetic fields in the sun's outer atmosphere -- the corona -- control both solar-wind acceleration and the dynamics of solar eruptions. We present the first clear observational evidence of coronal magnetic nulls in off-limb linearly…
Decayless kink oscillations of plasma loops in the solar corona may contain an answer to the enigmatic problem of solar and stellar coronal heating. The polarisation of the oscillations gives us a unique information about their excitation…
We aim at studying the small-scale evolution at the boundaries of an equatorial coronal hole connected with a channel of open magnetic flux with the polar region and an `isolated' one in the extreme-ultraviolet spectral range. We intend to…
Coronal holes are the darkest and least active regions of the Sun, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed…
This paper reviews the latest observational evidence for the existence of propagating waves in the open magnetic flux tubes of the solar corona. SOHO measurements have put tentative limits on the fluxes of various types of…
We report on the results of four convective dynamo simulations with an outer coronal layer. The magnetic field is self-consistently generated by the convective motions beneath the surface. Above the convection zone, we include a polytropic…
Alfven waves created by sub-photospheric motions or by magnetic reconnection in the low solar atmosphere seem good candidates for coronal heating. However, the corona is also likely to be heated more directly by magnetic reconnection, with…