Related papers: Gamma-ray bursts: a Centauro's cry?
Gamma-ray bursts (GRBs) are sources of energetic, highly variable fluxes of gamma rays, which demonstrates that they are powerful particle accelerators. Besides relativistic electrons, GRBs should also accelerate high-energy hadrons, some…
The energy released by the inner engine of GRBs can originate from structural readjustments inside a compact star. In particular, the formation of deconfined quark matter can liberate enough energy to power the burst. We show that the…
The sudden release of copious $\g$-ray photons into a compact region creates an opaque photon--lepton fireball due to the prolific production of electron--positron pairs. The photons that we observe in the bursts emerge only at the end of…
A new cosmological scenario for the origin of gamma ray bursts (GRBs) is proposed. In our scenario, a highly evolved central core in the dense galactic nucleus is formed containing a subsystem of compact stellar remnants (CSRs), such as…
The cosmological gamma-ray burst (GRB) model for the production of ultra- high energy cosmic rays is described, and the current observational evidence which support it discussed. Several predictions of the model are presented, which would…
There are strong indications that the process of conversion of a neutron star into a strange quark star proceeds as a strong deflagration implying that in a few milliseconds almost the whole star is converted. Starting from the…
In this contribution we briefly introduce a mechanism for short gamma ray burst emission different from the usually assumed compact object binary merger progenitor model. It is based on the energy release in the central regions of neutron…
Gamma-ray bursts are the most luminous explosions in the Universe. They appear connected to supernova remnants from massive stars or the merger of their remnants, and their brightness makes them temporarily detectable out to the larges…
According to the collapsar model, gamma-ray bursts are thought to be produced in shocks that occur after the relativistic jet has broken free from the stellar envelope. If the mass density of the collimated outflow is less than that of the…
We study the conversion of neutron matter into strange matter as a detonation wave. The detonation is assumed to originate from a central region in a spherically symmetric background of neutrons with a varying radial density distribution.…
Magnetars and many of the magnetar-related objects are summarized together and discussed. It is shown that there is an abuse of language in the use of "magnetar". Anomalous X-ray pulsars and soft gamma-ray repeaters are well-known magnetar…
Gamma-Ray Bursts (GRBs) - short bursts of 100-1MeV photons arriving from random directions in the sky are probably the most relativistic objects discovered so far. Still, somehow they did not attract the attention of the relativistic…
I summarize recent results about how a neutron star binary coalescence can produce short gamma-ray bursts (GRBs). Two possibilities are discussed: the annihilation of neutrino anti-neutrino pairs above the merged remnant and the exponential…
The origin of cosmic rays is still one of the unresolved questions in modern physics. Violent and high energetic explosions of {\gamma}-ray emission known as Gamma Ray Bursts (GRBs) are perhaps one of the main candidates of sources of…
Hydrogen and helium accreted onto a neutron star undergo thermonuclear burning. Explosive burning is observed as a type I X-ray burst. We describe the different burning regimes and focus on some of the current inconsistencies between theory…
This meeting covered the range of cosmic explosions from solar flares to gamma-ray bursts. A common theme is the role of rotation and magnetic fields. A rigorous examination is underway to characterize systematic effects that might alter…
We speculate that the universe is filled with stars composed of electromagnetic and dilaton fields which are the sources of the powerful gamma-ray bursts impinging upon us from all directions of the universe. We calculate soliton-like…
It is proposed that the gamma-ray photons that characterize the prompt emission of Gamma-Ray Bursts are produced through the Compton drag process, caused by the interaction of a relativistic fireball with a very dense soft photon bath. If…
Gamma ray bursts (GRBs) are astronomical phenomena detected at highest energies. The gamma ray photons carry energies on the order of mega-electronovolts and arrive to us from the point-like sources that are uniformly distributed on the…
The possible conversion of neutron matter to strange matter and its relevance to astrophysical problems are discussed. Particular attention is paid to the {\it form} in which this hypothetical burning process should be propagated in dense…