Related papers: The width, density and outflow of solar coronal st…
The tenuous supersonic solar wind that streams from the top of the corona passes through a natural boundary -- the Alfv\'en surface -- that marks the causal disconnection of individual packets of plasma and magnetic flux from the Sun…
Radio signals propagating via the solar corona and solar wind are significantly affected by compressive waves, impacting properties of solar bursts as well as sources viewed through the turbulent solar atmosphere. While static fluctuations…
Accurate forecasting of the solar wind has grown in importance as society becomes increasingly dependent on technology that is susceptible to space weather events. This work describes an inner boundary condition for ambient solar wind…
Various bright structures abound in the chromosphere playing an essential role in the dynamics and evolution therein. Tentatively identifying the wave characteristics in the outer solar atmosphere helps to understand this layer better. One…
Electromagnetic wave scattering off density inhomogeneities in the solar corona is an important process which determines both the apparent source size and the time profile of radio bursts observed at 1 AU. Here we model the scattering…
The solar corona is a complex system, with nonisothermal plasma and being in the self-gravitating field of the Sun. So the corona plasma is not only a nonequilibrium system but also a nonextensive one. We estimate the parameter of…
We identify more than ten steady sub-Alfv\'enic solar wind intervals from the measurements of the Parker Solar Probe (PSP) from encounter 8 to encounter 14. An analysis of these sub-Alfv\'enic intervals reveals similar properties and…
Modern radio telescopes are extremely sensitive to plasma on the line of sight from a radio source to the antenna. Plasmas in the corona and solar wind produce measurable changes in the radio wave amplitude and phase, and the phase…
We identify coronal holes using a histogram-based intensity thresholding technique and compare their properties to fast solar wind streams at three different points in the heliosphere. The thresholding technique was tested on EUV and X-ray…
Positive streamers in ambient air at pressures from 0.013 to 1 bar are investigated experimentally. The voltage applied to the anode needle ranges from 5 to 45 kV, the discharge gap from 1 to 16 cm. Using a "slow" voltage rise time of 100…
From 2022 March 18-21, active region (AR) 12967 was tracked simultaneously by Solar Orbiter (SO) at 0.35 au and Hinode/EIS at Earth. During this period, strong blue-shifted plasma upflows were observed along a thin, dark corridor of open…
Using MHD seismology by observed kink waves, the magnetic field profile of a coronal streamer has been investigated. STEREO-B/EUVI temporal image data on 7 March 2012 shows an evolution of two consecutive EUV waves that interact with the…
As the solar wind propagates through the heliosphere, dynamical processes irreversibly erase the signatures of the near-Sun heating and acceleration processes. The elemental fractionation of the solar wind should not change during transit…
Hydrodynamic simulations of granular convection predict the existence of supersonic flows covering ~3-4% of the solar surface at any time, but these flows have not been detected unambigously as yet. Using data from the spectropolarimeter…
A major obstacle for the understanding of long electrical discharges is the complex dynamics of streamer coronas, formed by many thin conducting filaments. Building macroscopic models for these filaments is one approach to attain a deeper…
The scale heights of stratification and the widths of steady solar coronal loops exhibit properties unexplained by standard theory: observed scale heights are often much greater than static theory predicts, while the nearly-constant widths…
Understanding many physical processes in the solar atmosphere requires determination of the magnetic field in each atmospheric layer. However, direct measurements of the magnetic field in the Sun's corona are difficult to obtain. Using…
A three dimensional (3D) tomographic reconstruction of the local differential emission measure (LDEM) of the global solar corona during the whole heliosphere interval (WHI, Carrington rotation CR-2068) is presented, based on STEREO/EUVI…
Plasma loops or plumes rooted in sunspot umbrae often harbor downflows with speeds of 100 km/s. These downflows are supersonic at transition region temperatures of 0.1 MK. The source of these flows is not well understood. We aim to…
Parameters of magnetic flux distribution inside low-latitude coronal holes (CHs) were analyzed. A statistical study of 44 CHs based on Solar and Heliospheric Observatory (SOHO)/MDI full disk magnetograms and SOHO/EIT 284\AA images showed…