Related papers: Annihilation emission from young supernova remnant…
Observations of the supernova remnant G22.7-0.2 in the field of view of W41 with the H.E.S.S. telescope array have resulted in evidence for a very high energy (VHE) gamma-ray emission from the direction of the object. The emission region is…
The SPI spectrometer aboard of the INTEGRAL satellite has released a map of the e+e- annihilation emission line of unprecedented quality, showing that most of the photons arise from a region coinciding with the stellar bulge of the Milky…
The Supernova Remnant (SNR) HESS J1731-347 displays strong non-thermal TeV gamma-ray and X-ray emission, thus the object is at present time accelerating particles to very high energies. A distinctive feature of this young SNR is the nearby…
While Tycho's supernova remnant is one of the most studied type Ia Galactic supernova remnants, a global view of the physical properties of its ejecta is lacking, to understand its mysteries. In particular, the spatial distribution of the…
A large fraction of core-collapse supernovae (CCSNe), 30-50%, are expected to originate from the low-mass end of progenitors with $M_{\rm ZAMS}~= 8-12~M_\odot$. However, degeneracy effects make stellar evolution modelling of such stars…
Observational data from the Fermi Gamma-ray Space Telescope are analyzed with a goal in mind to look for variations in gamma-ray flux from young shell-like supernova remnants. Uniform methodological approach is adopted for all SNRs…
Classical novae are important producers of radioactive nuclei, such as be7, n13, f18, na22 and al26. The disintegration of these nuclei produces positrons (except for be7) that through annihilation with electrons produce photons of energies…
While the definitive detection of gamma-rays from known supernova remnants (SNRs) remains elusive, the collection of unidentified EGRET sources that may be associated with SNRs has motivated recent modelling of TeV emission from these…
While supernova remnants (SNRs) are widely thought to be powerful accelerators, evidence comes largely from a small number of well-studied cases. Here we systematically determine the gamma-ray emission from all known Galactic SNRs,…
Modern imaging atmospheric Cherenkov telescopes have extensively observed young nearby supernova remnants (SNRs), with ages of about 1000 years or less, in the very-high-energy (VHE) gamma-ray band. These efforts resulted in the detection…
Supernova remnants (SNRs) have long been hypothesized as the main source of Galactic Cosmic Rays up to PeV energies. Some of them have indeed been shown to accelerate protons to TeV energies and above. But which of them are indeed efficient…
The discovery of a non-thermal radio ring of low surface brightness about one degree in diameter has been recently reported around the location in the sky of the Calvera pulsar, at a high Galactic latitude. The radio properties point to it…
Although supernova remnants remain the main suspects as sources of Galactic cosmic rays up to the knee, the supernova paradigm still has many loose ends. The weakest point in this construction is the possibility that individual supernova…
Supernova remnants (SNRs) are thought to be the most plausible sources of Galactic cosmic rays. One of the principal questions is whether they are accelerating particles up to the maximum energy of Galactic cosmic rays ($\sim$PeV). In this…
The measurement of gamma-ray lines from the decay chain of 56Ni provides unique information about the explosion in supernovae. The 56Ni freshly-produced in the supernova powers the optical light curve, as it emits gamma-rays upon its…
Classical novae emit gamma-ray radiation at 511 keV and below, with a cut-off at around (20-30) keV, related to positron annihilation and its Comptonization in the expanding envelope. This emission has been elusive up to now, because it…
We discuss the possibility that the recent detection of 511 keV gamma rays from the galactic bulge, as observed by INTEGRAL, can be naturally explained by the supermassive very dense droplets (strangelets) of dark matter. These droplets are…
As part of a systematic search programme of a 10-degree wide strip of the Northern Galactic plane we present preliminary evidence for the discovery of four (and possibly five) new supernova remnants (SNRs). The pilot search area covered the…
Synchrotron X-ray emission components were recently detected in many young supernova remnants (SNRs). There is even an emerging class - SN1006, RXJ1713.72-3946, Vela Jr, and others - that is dominated by non-thermal emission in X-rays, also…
We present the analysis of the X-ray data collected during an observation of the supernova remnant (SNR) MSH 11-62 by the Advanced Satellite for Cosmology and Astrophysics (ASCA). We show that MSH 11-62 is a composite remnant whose X-ray…