Related papers: Annihilation emission from young supernova remnant…
Supernova remnants (SNRs) are thought to be the primary sources of Galactic Cosmic Rays (CRs). In the last few years, the wealth of gamma-ray data collected by GeV and TeV instruments has provided important information about particle…
Superluminous supernovae (SLSNe) are among the most energetic stellar explosions, yet their central power source remains uncertain. Models invoking magnetar spin-down or circumstellar interaction predict GeV gamma-ray emission once the…
We present a detailed investigation of the $\gamma$-ray emission in the vicinity of the supernova remnant (SNR) W28 (G6.4$-$0.1) observed by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope. We detected significant…
Supernova remnants (SNRs) are the most attractive candidates for the acceleration sites of Galactic cosmic rays. We report the detection of GeV $\gamma$-ray emission with the Pass 8 events recorded by Fermi Large Area Telescope (Fermi-LAT)…
High energy (~GeV) positrons are seen within cosmic rays and observation of a narrow line at 511 keV shows that positrons are annihilating in the galaxy after slowing down to ~keV energies or less. Our state of knowledge of the origin of…
SN 1987A provides a unique opportunity to study the evolution of a supernova from explosion into very late phases. Due to the rich chemical structure, the multitude of physical process involved, and extensive radiative transfer effects,…
A deep hard X-ray survey of the INTEGRAL satellite first detected the non-thermal emission up to 90 keV in the Tycho supernova (SN) remnant. Its 3 -- 100 keV spectrum is fitted with a thermal bremsstrahlung of $kT\sim 0.81\pm 0.45$ keV plus…
It has long been speculated that supernova remnants represent a major source of cosmic rays in the Galaxy. Observations over the past decade have ceremoniously unveiled direct evidence of particle acceleration in SNRs to energies…
We search for far-infrared (FIR) counterparts of known supernova remnants (SNRs) in the Galactic plane (10 deg <| l |< 60 deg) at 70-500 micron using the Herschel Infrared Galactic Plane Survey (Hi-GAL). Of 71 sources studied, we find that…
The recently launched satellite, Fermi Gamma-ray Space Telescope, is expected to find out if cosmic-ray (CR) protons are generated from supernova remnants (SNRs), especially RX J1713.7-3946, by observing the GeV-to-TeV gamma-rays. The GeV…
MUSE-based emission-line maps of the spiral galaxy NGC 4030 reveal the existence of unresolved sources with forbidden line emission enhanced with respect to those seen in its own HII regions. This study reports our efforts to detect and…
The shock wave of supernova remnants (SNRs) and the wind termination shock in pulsar wind nebula (PWNe) are considered as prime candidates to accelerate the bulk of Galactic cosmic ray (CR) ions and electrons. The SNRs hosting a PWN (known…
The nebula J222557+601148, tentatively identified by Morris et al. (2006) as a young Galactic supernova remnant (SNR) from Spitzer Galactic First Look Survey images and a follow-up mid-infrared spectrum, is unlikely to be a SNR remnant…
We report results from deep observations (~750 ks) of Tycho's supernova remnant (SNR) with NuSTAR. Using these data, we produce narrow-band images over several energy bands to identify the regions producing the hardest X-rays and to search…
From radio and higher-frequency observations, more than 300 SNRs have been discovered in the Milky Way, of which 220 fall into the H.E.S.S. Galactic Plane Survey. However only 50 SNRs are coincident with a H.E.S.S source and in 8 cases the…
During its first year in orbit the INTEGRAL observatory performed deep exposures of the Galactic Center region and scanning observations of the Galactic plane. We report on the status of our analysis of the positron annihilation radiation…
Galactic cosmic ray (CRs) sources, classically proposed to be Supernova Remnants (SNRs), must meet the energetic particle content required by direct measurements of high energy CRs. Indirect gamma-ray measurements of SNRs with the Fermi…
The synchrotron radiation from secondary electrons and positrons (SEPs) generated by hadronic interactions in the shock of supernova remnant (SNR) could be a distinct evidence of cosmic ray (CR) production in SNR shocks. Here we provide a…
Magnetic reconnection in current layers that form intermittently in radiatively inefficient accretion flows onto black holes is a promising mechanism for particle acceleration and high-energy emission. It has been recently proposed that…
We obtain the spectrum of gamma ray emissions from the moduli whose decay into $e^+ e^-$ accounts for the 511 keV line observed by SPI/INTERGRAL. The moduli emit gamma rays through internal bremsstrahlung, and also decay directly into two…