Related papers: Magnetar giant flare high-energy emission
Magnetar Giant Flares (MGFs) are the most energetic non-catastrophic transients known to originate from stellar objects. The first discovered events were nearby. In recent years, several extragalactic events have been identified, implying…
Transient X-ray emission, with an approximate t^{-0.7} decay, was observed from SGR 1900+14 over 40 days following the the giant flare of 27 Aug 1998. We calculate in detail the diffusion of heat to the surface of a neutron star through an…
The Compton Gamma-Ray Observatory (CGRO) experiments EGRET and COMPTEL observed the Virgo sky region continuously for 7 weeks between December 10, 1996 and January 28, 1997. The prominent quasar 3C~273 was found to be the brightest source…
Pulsed emission from gamma-ray pulsars originates inside the magnetosphere, from radiation by charged particles accelerated near the magnetic poles or in the outer gaps. In polar cap models, the high energy spectrum is cut off by magnetic…
The process responsible for the Chandra-detected X-ray emission from the large scale jets of powerful quasars is a matter of ongoing debate. The two main contenders are external Compton (EC) scattering off the cosmic microwave background…
The knowledge of the rate of soft gamma-ray repeater (SGR) giant flares is important for understanding the giant flare mechanism and the SGR energy budget in the framework of the magnetar model. We estimate the upper limit to the rate using…
This paper discusses several aspects of current research on high energy emission from supernova remnants, covering the following main topics: 1) The recent evidence for magnetic field amplification near supernova remnant shocks, which makes…
Neutron stars with very strong magnetic fields are known as magnetars. There are multiple theories that predict magnetars may be able to emit high-energy (HE) neutrinos through hadronic processes by accelerating cosmic rays to high…
In this paper we study the generation of high energy emission from normal pulsars. For this purpose we consider the particles accelerated in the outer magnetosphere sliding along the closed magnetic field lines. It has been shown that in…
Extremely bright coherent radio bursts with millisecond duration, reminiscent of cosmological fast radio bursts (FRBs), were co-detected with anomalously-hard X-ray bursts from a Galactic magnetar SGR 1935$+$2154. We investigate the…
It is conjectured that coherent re-emission of cyclotron resonance absorption could result in pulsar giant pulses. This conjecture seems reasonable as it can naturally explain the distribution of pulsars with giant pulses on the…
Simultaneous Swift and Fermi observations of gamma-ray bursts (GRBs) offer a unique broadband view of their afterglow emission, spanning more than ten decades in energy. We present the sample of X-ray flares observed by both Swift and Fermi…
Two classes of high energy sources in our galaxy are believed to host magnetars, neutron stars whose emission results from the dissipation of their magnetic field. The extremely high magnetic field of magnetars distorts their shape, and…
In the last few years the Fermi -LAT instrument has detected GeV gamma-ray emission from a few novae. Such GeV emission can be interpreted in terms of an inverse Compton process of electrons accelerated in a shock. It is expected that…
We propose a time-dependent one-zone model based on a quasi-Maxwellian `pile-up' distribution in order to explain the time-averaged high energy emission of TeV blazars. The instantaneous spectra are the result of the synchrotron and…
Magnetars younger than one century are expected to be hyper active. Besides winds powered by rotation they generate frequent magnetic flares, which launch powerful blast waves into the wind. These internal shocks act as masers producing…
(abridged) Although discovered 40 years ago, the emission mechanism responsible for the observed pulsar radiation remains unclear. However, the high-energy pulsed emission is usually explained in the framework of either the polar cap or the…
Recurrent novae occurring in symbiotic binaries are candidate sources of high energy photons, reaching GeV energies. Such emission is a consequence of particle acceleration leading to pion production. The shock between matter ejected by the…
Fermi has detected gamma-ray emission from eight globular clusters. We suggest that the gamma-ray emission from globular clusters may result from the inverse Compton scattering between relativistic electrons/positrons in the pulsar wind of…
The magnetosphere of strongly magnetized neutron stars, such as magnetars, can sustain large electric currents. The charged particles return to the surface with large Lorentz factors, producing a particle bombardment. We investigate the…