Related papers: Gamma-ray binaries
Gamma-ray bursts are the most concentrated explosions in the Universe. They have been detected electromagnetically at energies up to tens of GeV, and it is suspected that they could be active at least up to TeV energies. It is also…
Data from the 3B Catalogue suggest that short and long GRB are the results of different classes of events, rather than different parameter values within a single class: Short bursts have harder spectra in the BATSE bands, but chiefly long…
Recent observations of blazars at high energy (HE, 0.1-100 GeV) and very high energy (VHE, >0.1 TeV) have provided important constraints on the intensity and spectrum of the diffuse Extragalactic Background Light (EBL), shedding light on…
The Universe is largely transparent to $\gamma$ rays in the GeV energy range, making these high-energy photons valuable for exploring energetic processes in the cosmos. After seven years of operation, the Fermi {\it Gamma-ray Space…
In the recent years, the discovery of a new class of Galactic transients with fast and bright flaring X-ray activity, the Supergiant Fast X-ray Transients, has completely changed our view and comprehension of massive X-ray binaries. These…
We present the most recent results from our investigation on Supergiant Fast X-ray Transients, a class of High-Mass X-ray Binaries, with a possible counterpart in the gamma-ray energy band. Since 2007 Swift has contributed to this new field…
The prompt emission of the gamma-ray bursts is found to be very energetic, releasing ~10^51 ergs in a flash. However, their emission mechanism remains unclear and understanding their spectra is a key to determining the emission mechanism.…
Galactic microquasars are certainly one of the most recent additions to the field of high energy astrophysics and have attracted increasing interest over the last decade. However, the high energy part of the spectrum of microquasars is the…
Gamma-ray binaries are thought to be composed of a young pulsar in orbit around a massive O or Be star, with their gamma-ray emission powered by pulsar spindown. The number of such systems in our Galaxy is not known. We aim to estimate the…
Over the past few decades impressive progress has been made in the field of photon polarimetry, especially in the hard X-ray and soft gamma-ray energy regime. Measurements of the linear degree of polarization for some of the most energetic…
There are only a few sources that are definitely known to be gamma-ray binaries. Two of these are listed as associations in the Fermi LAT Bright Source List. We are developing novel techniques to extract high signal-to-noise light curves of…
We investigate the spectral properties of the brightest gamma-ray flares of blazars detected by the Fermi Large Area Telescope. We search for the presence of spectral breaks and measure the spectral curvature on typical time scales of a few…
In this chapter we review some aspects of X-ray binaries, particularly those presenting steady jets, i.e. microquasars. Because of their proximity and similarities with active galactic nuclei (AGN), galactic jet sources are unique…
The modeled performance of the Alpha Magnetic Spectrometer (AMS) as a high energy (0.3 to 100 GeV) gamma-ray detector is described, and its gamma ray astrophysics objectives are discussed.
X-ray binaries are binary star systems in which a compact object (a neutron star or a black hole) and a relatively normal star orbit a common centre of mass. Since the discovery of X-ray binaries with the first X-ray telescopes in the…
Recently, tentative evidence for an excess of gamma rays at energies around 130 GeV has been reported from analyses of data from the Fermi Large Area Telescope (LAT). The excess is potentially of great interest, as it could be associated…
``Adding colour'' to the gravitational-wave sky by probing unexplored frequency bands has the potential to unveil new and unexpected phenomena in the Universe. In these proceedings, we summarise current efforts to probe gravitational waves…
Gamma-ray burst sources with a high luminosity can produce electron-positron pair cascades in their environment as a result of back-scattering of a seed fraction of their original hard spectrum. The resulting spectral modifications offer…
Gamma-ray instrumentation for astronomical spectroscopy consists of multiple-interaction detectors in space combined with sophisticated post-processing of detector events on ground. Spectral signatures in the MeV regime originate from…
The Cannon-Ball model of Gamma-Ray Bursts and their afterglows--described in the text and in innumerable previous occasions--is extremely successful and predictive. In a few intrinsically bright GRBs, gamma-rays with energies in the TeV…