Related papers: Possible generation of $\gamma$-ray laser by elect…
Scattering relativistic electrons with optical lasers can result in a significant frequency upshift for the photons, potentially producing $\gamma$-rays. This is what linear Compton scattering taught us. Ultra-intense lasers offer nowadays…
The motion of channeled particles is accompanied by the photon emission. This feature can be used for the stimulated generation of high energy photons, but the required density of channeled particles must be very high.
I argue that cosmic Gamma-ray Bursts (GRB) may be produced by collapses or mergers of stars made of `mirror' matter. The mirror neutrinos (which are sterile for our matter) produced at these events can oscillate into ordinary neutrinos. The…
The progressive development of high power lasers over the last several decades, enables the study of $\gamma$-photon generation when an intense laser beam interacts with matter, mainly via inverse Compton scattering at the high intensity…
A coherent x-ray or gamma ray can be created from a dense electron beam propagating through an intense laser undulator. It is analyzed by using the Landau damping theory which suits better than the conventional linear analysis for the free…
We present a new and efficient method of generating twisted gamma rays utilizing highly accelerated helium-like ions; they are excited to a chosen state by irradiating two optical lasers and emit a photon with orbital angular momentum in…
It is proposed that gamma-ray bursts are created in the mergers of double neutron star binaries and black hole neutron star binaries at cosmological distances. Bursts with complex profiles and relatively long durations are the result of…
Quantum electrodynamics in a laser is formulated, in which the electron-laser interaction is exactly considered, while the interaction of an electron and a single photon is considered by perturbation. The formulation is applied to the…
The mechanism by which gamma-ray pulsars shine might be reproducible in a laboratory. This claim is supported by three observations: (i) properly focusing a few PW optical laser gives an electromagnetic field in the so-called Aristotelian…
Clusters of galaxies and the large scale filaments that connect neighboring clusters are expected to be sites of acceleration of charged particles and sources of non-thermal radiation from radio frequencies to gamma rays. Gamma rays are…
We explore the possibility that the diffuse gamma-ray background radiation (GBR) at high galactic latitudes could be dominated by inverse Compton scattering of cosmic ray (CR) electrons on the cosmic microwave background radiation and on…
The origin of the extragalactic gamma-ray background is a pressing cosmological mystery. The Fermi Gamma-Ray Space Telescope has recently measured the intensity and spectrum of this background; both are substantially different from previous…
Blazar emission of gamma rays and cosmic ray production of gamma rays in gas-rich clusters have been proposed recently as alternative sources of the high energy extragalactic diffuse gamma ray background radiation. We show that these…
We propose that repeated photoexcitation/ionization of high Z atoms of highly relativistic flows by star light in dense stellar regions followed by emission of decay/recombination photons, which are beamed and boosted to gamma ray energies…
Ultra-intense lasers are expected to produce, in near future, relativistic electron-positron plasma droplets. Considering the local photon production rate in complete leading order in quantum electrodynamics (QED), we point out that these…
Laser produced $gamma$-photons can make an important impact on applied and fundamental physics that require high $gamma$-photon yield and strong collimation. We propose addition of a constant magnetic field to the laser-solid interaction to…
One of the remarkable phenomena in the laser-matter interaction is the extremely efficient energy transfer to $\gamma$-photons, that appears as a collimated $\gamma$-ray beam. For interactions of realistic laser pulses with matter,…
It is demonstrated that targets with a broken rotational symmetry may facilitate generation of a strong axial (poloidal) magnetic field. An intense laser beam irradiating such a target creates intense electron currents carrying vorticity…
Some aspects of theory of gamma-ray production in blazar type active galaxies are discussed in the context of recent observations.
The gamma-ray background is still a subject under great debate. All phenomena in the universe emitting gamma-rays can contribute directly as diffuse emission or as an isotropic component from unresolved point sources. The question of the…