Related papers: Generation of large scale electric fields in coron…
Coronae express different facets of their energy release processes in different wavelength regions. While soft X-ray and EUV emission dominates the radiative losses of the thermal plasma, hard X-ray emission (>10 keV) can be produced from…
The formation of electron groups is a common phenomenon in gas discharges and space plasmas. We describe similarities between electron kinetics in solar wind, cathode region of glow discharges, and magnetic nozzles. Remarkable resemblances…
We discuss that energetic electrons are generated near the X-type magnetic reconnection region due to a surfing acceleration mechanism. In a thin plasma sheet, the polarization electric fields pointing towards the neutral sheet are induced…
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…
Solar flares and coronal mass ejections are associated with rapid changes in field connectivity and powered by the partial dissipation of electrical currents in the solar atmosphere. A critical unanswered question is whether the currents…
Solar microflares are ubiquitous in the solar corona, yet their driving mechanisms remain a subject of ongoing debate. Using high-resolution coronal observations from the Solar Orbiter's Extreme Ultraviolet Imager (EUI), we identified about…
Surface magnetism is believed to be the main driver of coronal heating and stellar wind acceleration. Coronae are believed to be formed by plasma confined in closed magnetic coronal loops of the stars, with winds mainly originating in open…
We numerically explore electron acceleration and coronal heating by dissipative electric fields. Electrons are traced in linear force-free magnetic fields extrapolated from SOHO/MDI magnetograms, endowed with anomalous resistivity ($\eta$)…
It is found by using the gyrokinetic theory that significant radial electric fields, or zonal flows, can be generated by the radial redistribution of energetic ion pressure in a tokamak fusion device. Trapped energetic ions are more…
Sandstorms are frequently accompanied by the generation of intense electric fields and lightning. In a very narrow region close to the ground level, sand particles undergo a charge exchange mechanism whereby larger (resp. smaller) sized…
The magnetic field of the Sun is the underlying cause of the many diverse phenomena combined under the heading of solar activity. Here we describe the magnetic field as it threads its way from the bottom of the convection zone, where it is…
The solar corona has been revealed in the past decade to be a highly dynamic nonequilibrium plasma environment. Both the loop-filled coronal base and the extended acceleration region of the solar wind appear to be strongly turbulent, but…
First I emphasize the magnetospheric loop current system induced by the wind activity. Next, I address the formation of the field-aligned electric field. An interesting aspect is the reaction of the inner magnetosphere to an induced…
The energy released in solar flares derives from a reconfiguration of magnetic fields to a lower energy state, and is manifested in several forms, including bulk kinetic energy of the coronal mass ejection, acceleration of electrons and…
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…
A theory for the generation of current in a toroidal plasma by radio-frequency waves is presented. The effect of an opposing electric field is included, allowing the case of time varying currents to be studied. The key quantities that…
Solar flares and coronal mass ejections (CMEs) are the most powerful explosions in the Sun. They are major sources of potentially destructive space weather conditions. However, the possible causes of their initiation remain controversial.…
The energy release and build-up processes in the solar corona have significant implications in particular for the case of large recurrent flares, which pose challenging questions about the conditions that lead to the episodic energy release…
We study the effect of newly emerged solar active regions (ARs) on the large-scale magnetic environment of pre-existing ARs (PEARs). We first present a theoretical approach to quantify the "interaction energy" between new ARs and PEARs as…
As one of the most spectacular energy release events in the solar system, solar flares are generally powered by magnetic reconnection in the solar corona. As a result of the re-arrangement of magnetic field topology after the reconnection…