Related papers: Harmonic Electron Cyclotron Maser Emission along t…

EUV imaging observations from several space missions (SOHO/EIT, TRACE, and SDO/AIA) have revealed a presence of propagating intensity disturbances in solar coronal loops. These disturbances are typically interpreted as slow magnetoacoustic…

We study the chromosphere and corona of the ultra-fast rotator AB Dor A at high temporal and spectral resolution using simultaneous observations with XMM-Newton in the X-rays, VLT/UVES in the optical, and the ATCA in the radio. Our optical…

Three-wave interactions between Langmuir and electromagnetic waves in plasma with unstable electron flows are believed to be the main cause for type II and III solar radio emissions. The narrow band of type II bursts requires to assume that…

A complete understanding of the onset and subsequent evolution of confined flares has not been achieved. Earlier studies mainly analyzed disk events so as to reveal their magnetic topology and cause of confinement. In this study, taking…

Coronal loops, constituting the basic building blocks of the active Sun, serve as primary targets to help understand the mechanisms responsible for maintaining multi-million Kelvin temperatures in the solar and stellar coronae. Despite…

In this article, we compare the properties of two coronal mass ejections (CMEs) that show similar source region characteristics but different evolutionary behavior in the later phases. We discuss the two events in terms of their near-Sun…

Here we experimentally map the dynamics of electron plasma waves in laser solid interaction. We do time resolved measurements of second harmonic and hard X-ray generation from interaction of intense ($10^{16} W cm^{-2}$, 100 fs, 800nm)…

Coronal waves exist ubiquitously in the solar atmosphere. They are important not only in their own rich physics but also essential candidates of triggering magnetic eruptions in the remote. However, the later mechanism has never been…

Magnetic AB stars are known to produce periodic radio pulses by the electron cyclotron maser emission (ECME) mechanism. Only 19 such stars, known as 'Main-sequence Radio Pulse emitters' (MRPs) are currently known. The majority of MRPs have…

We report on a theoretical study on the rise of strong peaks at the harmonics of the cyclotron resonance in the irradiated magnetoresistance in ultraclean two-dimensional electron systems. The motivation is the experimental observation of a…

Energetic X-ray radiations emitted from various accretion systems are widely considered to be produced by Comptonization in the hot corona. The corona and its interaction with the disc play an essential role in the evolution of the system…

We study the propagation properties of slow magneto-acoustic waves in a multi-thermal coronal loop using a 3D MHD model, for the first time. A bundle of 33 vertical cylinders, each of 100{\,}km radius, randomly distributed over a circular…

We report broadband spectral properties of the high mass X-ray binary pulsar SMC X-2 by using three simultaneous $NuSTAR$ and $Swift$/XRT observations during its 2015 outburst. The pulsar was significantly bright, reaching a luminosity up…

Coronal loops act as resonant cavities for low frequency fluctuations that are transmitted from the deeper layers of the solar atmosphere and are amplified in the corona, triggering nonlinear interactions. However trapping is not perfect,…

Twisted coronal loops in the solar atmosphere may become kink-unstable when their magnetic field lines are sufficiently twisted. This instability can trigger magnetic reconnection, leading to the emission of electromagnetic radiation, which…

The outer atmosphere of the Sun is composed of plasma heated to temperatures well in excess of the visible surface. We investigate short cool and warm (<1 MK) loops seen in the core of an active region to address the role of field-line…

Recent Solar Dynamic Observatory observations reveal that coronal mass ejections (CMEs) consist of a multi-temperature structure: a hot flux rope and a cool leading front (LF). The flux rope first appears as a twisted hot channel in the…

We discuss a mechanism for intense electromagnetic wave emission at an astrophysical relativistic shock in a magnetized collisionless plasma. At the magnetized shock, the particle reflection by a compressed magnetic field of the shock…

Flares close to the solar limb, where the footpoints are occulted, can reveal the spectrum and structure of the coronal loop-top source in X-rays. We aim at studying the properties of the corresponding energetic electrons near their…

The 1998 April 20 spectral line data from the Coronal Diagnostics Spectrometer (CDS) on the {\it Solar and Heliospheric Observatory} (\SOHO) shows a coronal loop on the solar limb. Our original analysis of these data showed that the plasma…