Related papers: Coronal Holes
Solar flare electron acceleration is an efficient process, but its properties (mechanism, location) are not well constrained. Via hard X-ray (HXR) emission, we routinely observe energetic electrons at the Sun, and sometimes we detect…
Although the origins of slow solar wind are unclear, there is increasing evidence that at least some of it is released in a steady state on over-expanded coronal hole magnetic field lines. This type of slow wind has similar properties to…
Both coronal holes and active regions are source regions of the solar wind. The distribution of these coronal structures across both space and time is well known, but it is unclear how much each source contributes to the solar wind. In this…
Slow magnetoacoustic waves in a static background provide a seismological tool to probe the solar atmosphere in the analytic frame. By analyzing the spatiotemporal variation of the electron number density of plume structure in coronal holes…
We analyze a large, complex equatorial coronal hole (ECH) and its immediate surroundings with a focus on the roots of the fast solar wind. We start by demonstrating that our ECH is indeed a source of the fast solar wind at 1AU by examining…
We use the first publically available data from the Daniel K. Inouye Solar Telescope (DKIST) to track magnetic connections from the solar photosphere into the corona. We scrutinize relationships between chromospheric magnetism and bright…
This paper presents results of comparison between observations of coronal holes in the UV (SOHO EIT) and microwave emission (17, 5.7 GHz, 327 and 150.9 MHz, NoRH, SSRT and Nancy radioheliographs), and solar wind parameters, according to the…
Coronal loops, seen in solar coronal images, are believed to represent emission from magnetic flux tubes with compact cross-sections. We examine the 3D structure of plasma above an active region in a radiative magnetohydrodynamic simulation…
To study the dynamics of coronal holes and the role of waves in the acceleration of the solar wind, spectral observations were performed over polar coronal hole regions with the SUMER spectrometer on SoHO and the EIS spectrometer on Hinode.…
We investigate the occurrence of a CME-driven coronal dimming using unique high resolution spectral images of the corona from the Hinode spacecraft. Over the course of the dimming event we observe the dynamic increase of non-thermal line…
The EUI instrument on the Solar Orbiter spacecraft has obtained the most stable, high-resolution images of the solar corona from its orbit with a perihelion near 0.4 AU. A sequence of 360 images obtained at 17.1 nm, between 25-Oct-2022…
Poynting flux generated by random shuffling of photospheric magnetic footpoints is transferred through the upper atmosphere of the Sun where the plasma is heated to over 1 MK in the corona. High spatiotemporal resolution observations of the…
Absorbtion of Alfven waves is considered to be the main mechanism of heating in the solar corona. It is concluded that the sharp increase of the plasma temperature by two orders of magnitude is related to a self-induced opacity with respect…
The Sun's corona, heated to temperatures exceeding one million Kelvin despite lying above the cooler photosphere, has puzzled astrophysicists since its discovery in the 1940s. Prevailing theories, based on acoustic and magnetohydrodynamic…
The physical processes causing energy exchange between the Sun's hot corona and its cool lower atmosphere remain poorly understood. The chromosphere and transition region (TR) form an interface region between the surface and the corona that…
Recent observations revealed that the solar atmosphere is highly structured in density, temperature and magnetic field. The presence of these gradients may lead to the appearance of currents in the plasma, which in the weakly collisional…
The corona is a key component of most luminous accreting black holes, carrying 5 - 30 % of the power and in non-jetted Active Galactic Nuclei (AGN), creating all the X-ray emission above $\simeq 1-2$ keV. Its emission illuminates the inner…
Regular remote sensing of the magnetic field embedded within the million-degree solar corona is severely lacking. This reality impedes fundamental investigations of the nature of coronal heating, the generation of solar and stellar winds,…
The heating of the plasma in the solar atmosphere is discussed within both frameworks of fluid and kinetic drift wave theory. We show that the basic ingredient necessary for the heating is the presence of density gradients in the direction…
The solar wind consists of continuous streams of charged particles that escape into the heliosphere from the Sun, and is split into fast and slow components, with the fast wind emerging from the interiors of coronal holes. Near the ecliptic…