相关论文: Thin current sheet behind the dipolarization front
Sunspot proper motions and flares of a super active region NOAA 5395, which was the biggest and the most flare-active region in the 22nd sunspot cycle, were analyzed in details. We measured sunspot proper motions by using the H-alpha - 5.0…
Using multipoint Magnetospheric Multiscale (MMS) observations in an unusual string-of-pearls configuration, we examine in detail observations of the reformation of a fast magnetosonic shock observed on the upstream edge of a foreshock…
Aims. To investigate the magnetic field geometry and waves in the region near the Sun where the heliospheric current sheet is formed. Methods. One good example of apparent open and closed field lines was found and its fields and plasmas…
Magnetic Clouds (MCs) are a particular subset of Interplanetary Coronal Mass Ejections (ICMEs), forming large scale magnetic flux ropes. In this work we analyze the evolution of a particular MC (observed on March 1998) using {\it in situ}…
We report the detection of polarized emission in the vicinity of the Galactic center for 158 positions within eight different pointings of the Hertz polarimeter operating on the Caltech Submillimeter Observatory. These pointings include…
Steep gradients of temperature and density, called cold fronts, are observed by Chandra in a leading edge of subclusters moving through the intracluster medium (ICM). The presence of cold fronts indicates that thermal conduction across the…
The recent realization that Sweet-Parker current sheets are violently unstable to the secondary tearing (plasmoid) instability implies that such current sheets cannot occur in real systems. This suggests that, in order to understand the…
Moving magnetic features (MMFs) are small-size magnetic elements that are seen to stream out from sunspots, generally during their decay phase. Several observational results presented in the literature suggest them to be closely related to…
We present a simulated cluster of galaxies, modeled with a pre-heated intracluster medium, that exhibits X-ray features similar to the `cold fronts' seen in Chandra observations. Mock observations at a particular epoch show factor two…
Solar filaments can undergo eruptions and result in the formation of coronal mass ejections (CMEs), which could significantly impact planetary space environments. Observations of eruptions involving polar crown filaments, situated in the…
Hot flow anomalies (HFAs) represent a subset of solar wind discontinuities interacting with collisionless bow shocks. They are typically formed when the normal component of motional (convective) electric field points toward the embedded…
Magnetohydrodynamic configurations with strong localized current concentrations and vortices play an important role for the dissipation of energy in space and astrophysical plasma. Within this work we investigate the relation between…
Filaments/prominences are cold plasma (~ 10000 K) embedded in the solar corona, two orders of magnitude hotter. Filament plasma is structured by the magnetic field in thin elongated threads. Counter-streaming flows have been observed. The…
We present an analysis of a highly asymmetric cluster merger from a Chandra observation of Abell 85. The merger shows significant disruption of the less massive subcluster from ram pressure effects. Nevertheless, a cold core, coincident…
We report multi-wavelength and multi-viewpoint observations of a solar eruptive event which involves loop-loop interactions. During a C2.0 flare, motions associated with inflowing and outflowing plasma provide evidence for ongoing magnetic…
Magnetic active regions on the Sun are harbingers of space weather events. Understanding the physics of how they form and evolve will improve space weather forecasting. Our aim is to characterise the surface magnetic field and flows for a…
We present 1.5D Vlasov code simulations of the dynamics of electron holes in non-uniform magnetic and electric fields typical of current sheets and, particularly, of the Earth's magnetotail current sheet. The simulations show that spatial…
The Earth's magnetotail is characterized by stretched magnetic field lines. Energetic particles are effectively scattered due to the field-line curvature, which then leads to isotropization of energetic particle distributions and particle…
The effects of the heliospheric current sheet (HCS) on the evolution of Alfv\'enic turbulence in the solar wind are studied using MHD simulations incorporating the expanding-box-model (EBM). The simulations show that near the HCS, the…
Certain solar flares exhibit a distinctive candle-flame or cusp-shaped feature above the bright flare arcade visible in extreme ultraviolet (EUV) and X-ray channels sensitive to high-temperature plasma. The presence of a cusp-like structure…