Related papers: Galactic Superluminal Sources
The study of relativistic particle acceleration is a major topic of high-energy astrophysics. It is well known that massive black holes in active galaxies can release a substantial fraction of their accretion power into energetic particles,…
The superluminal X-ray transient source GRS 1915+105 was observed during July 20-29, 1996 with the Indian X-ray Astronomy Experiment (IXAE) on the Indian satellite IRS-P3 launched on March 21, 1996 from Shriharikota Range in India. During…
Relativistic outflows are a common phenomenon in accreting black holes. Despite the enormous differences in scale, stellar-mass black holes in X-ray binaries and collapsars, and super-massive black holes at the dynamic centre of galaxies…
Microquasars are compact objects (stellar-mass black holes and neutron stars) that mimic, on a smaller scale, many of the phenomena seen in quasars. Their discovery provided new insights into the physics of relativistic jets observed…
Microquasars, X-ray binaries displaying relativistic jets driven by accretion onto a compact object, are some of the most efficient accelerators in the Galaxy. Theoretical models predict Very High Energy (VHE) emission at the base of the…
The black hole MAXI J1820+070 was discovered during its 2018 outburst and was extensively monitored across the electromagnetic spectrum. Following the detection of relativistic radio jets, we obtained four Chandra X-ray observations taken…
Microquasars, X-ray binary systems that generate relativistic jets, were discovered in our Galaxy in the last decade of the XXth century. Their name indicates that they are manifestations of the same physics as quasars but on a completely…
GRO J1655--40 is a galactic microquasar, i.e. a short-period binary with relativistic radio-jets and where the companion is a black-hole. A little after its discovery in 1994 by $BATSE$, a distance of 3.2$\pm$0.2 kpc has been estimated, and…
The origin of Galactic cosmic rays (CRs) is unknown even though they have traditionally been connected to supernovae based on energetic arguments. In the past decades, Galactic black holes in X-ray binaries (BHXBs) have been proposed as…
The advent of new generation radio telescopes is opening new possibilities on the classification and study of extragalactic high-energy sources, specially the underrepresented ones like radio galaxies. Among these, Giant Radio Galaxies…
The jets of GRS 1915+105 carry a considerable energy away from the central source into the ISM. The similarity of the jets of this source and jets in radio galaxies or radio-loud quasars suggests that we should detect large-scale,…
A subset of ultraluminous X-ray sources (those with luminosities < 10^40 erg/s) are thought to be powered by the accretion of gas onto black holes with masses of ~5-20 M_solar, probably via an accretion disc. The X-ray and radio emission…
Presently there are several classes of detected gamma-ray extragalatic sources. They are mostly associated to active galactic nuclei (AGN) and (at soft gamma rays) to gamma-ray bursts (GRB), but not only. Active galactic nuclei consist of…
Microquasars are compact binary systems hosting collimated relativistic jets. They have long been proposed as cosmic-ray accelerators, probed via the gamma-ray emission produced by relativistic particles. However, the observational evidence…
Microquasars are X-ray binary stars with the capability to generate relativisticjets. It is expected that microquasars are gamma-ray sources, because of the analogy with quasars and because the theoretical models predict emission at such…
Microquasars, Galactic binary systems showing extended and variable radio emission, are potential gamma-ray emitters. Indications of gamma-ray transient episodes have been reported in at least two systems, Cyg X-1 and Cyg X-3. The…
GRS 1915+105 has exhibited at least three modes of long-wavelength (infrared to radio) flares. Class A flares are the bright ($\sim 1$ Jy) radio events whose apparent superluminal motion in many ways defines the microquasars. Class B flares…
The galactic superluminal motion source GRS 1915+105 was observed with RXTE at several occasions during its ongoing active state. The observed X-ray intensity changes drastically on a variety of time scales ranging from sub-seconds to days.…
The Italian gamma-ray satellite AGILE has recently reported the detection of some variable high-energy sources likely of galactic origin. These sources do not have any obvious counterpart at lower energies. We propose that these sources are…
We propose that relativistic Galactic jets like those observed in GRS 1915+105 and GRO J1655-40 may produce small but measurable contributions to the cosmic ray (CR) spectrum. If these jets contain cold protons and heavy ions (as in SS433),…