Related papers: Pair Production Detectors for Gamma-ray Astrophysi…
A previously unexplored experimental scheme is presented for generating low-divergence, ultra-dense, relativistic, electron-positron beams using 400 GeV/c protons available at facilities such as HiRadMat and AWAKE at CERN. Preliminary…
Several cosmic ray experiments have measured excesses in electrons and positrons, relative to standard backgrounds, for energies from ~ 10 GeV - 1 TeV. These excesses could be due to new astrophysical sources, but an explanation in which…
The production of high-energy astrophysical neutrinos is tightly linked to the emission of hadronic gamma-rays. I will discuss the recent observation of TeV to PeV neutrinos by the IceCube Cherenkov telescope in the context of gamma-ray…
We discuss the possibility of observing ultra high energy cosmic ray sources inhigh energy gamma rays. Protons propagating away from their accelerators produce secondary electrons during interactions with cosmic microwave background…
The large intensity of greater than 10 GeV positrons which apparently come from sources outside the Earth-Sun system observed recently by many spacecraft (PAMELA, FERMI, AMS2) is still a mystery with broad implications. In our attempts to…
Compton scattering of photons off high-energy electrons is a fundamental quantum mechanical process widely utilized to produce a $\gamma$-ray beam for scientific research. Instead of injecting laser light into a storage ring as a…
Ultra strong electromagnetic fields can lead to spontaneous creation of single or multiple electron-positron pairs. A quantum field theoretical treatment of the pair creation process combined with numerical methods provides a description of…
High-energy photons (above the MeV) are a powerful probe for astrophysics and for fundamental physics under extreme conditions. During the recent years, our knowledge of the high-energy gamma-ray sky has impressively progressed thanks to…
We discuss pair creation in a strong laser background. Using lightfront field theory, we show that all the physics is contained in the lightfront momentum transfer from the laser, and probe, to the produced pair. The dependence of this…
The all-sky survey in high-energy gamma rays (E$>$30 MeV) carried out by the Energetic Gamma Ray Experiment Telescope (EGRET) aboard the Compton Gamma-Ray Observatory provides a unique opportunity to examine in detail the diffuse gamma-ray…
The mechanism of laser-driven relativistic pair-jet production qualitatively changes as laser intensity exceeds $I\gtrsim5\times10^{22}$ W/cm$^{2}$ because of the appearance of laser-induced strong-field QED processes. Here, we show that by…
We consider the details of the QED processes that create electron-positron pairs in magnetic fields approaching and exceeding 10^{14} G. The formation of free and bound pairs is addressed, and the importance of positronium dissociation by…
If at least one neutron star (NS) is magnetized in a binary NS merger, then the orbital motion of the conducting companion during the final inspiral induces a strong voltage and current along the magnetic field lines connecting the NSs. If…
Electron-positron pair production in combined laser and Coulomb fields is studied. To this end, the Feynman diagram for multiphoton pair creation by muon impact on a circularly polarized high-frequency laser beam is evaluated within the…
The energy domain between 10 MeV and hundreds of GeV is an essential one for the multifrequency study of extreme astrophysical sources. The understanding of spectra of detected gamma rays is necessary for developing models for acceleration,…
Launched on June 11, 2008, the LAT instrument onboard the $Fermi$ Gamma-ray Space Telescope has provided a rare opportunity to study high energy photon emission from gamma-ray bursts. Although the majority of such events (27) have been iden…
Recently the Fermi-LAT data have revealed two gamma-ray emitting bubble-shaped structures at the Galactic center. If the observed gamma rays have hadronic origin (collisions of accelerated protons), the bubbles must emit high energy…
In the last few years the Fermi-LAT instrument has detected GeV gamma-ray emission from several novae. Such GeV emission can be interpreted in terms of inverse Compton emission from electrons accelerated in the shock or in terms of emission…
In this article we review a theoretical framework for pair production from strong external electromagnetic fields. We propose a numerical method to solve the resulting equations of motion and present results for both cases of spatially…
We search for gamma-ray emission from 114 Galactic high mass X-ray binaries, including 4 well studied catalogued sources, in 12.5 years of Fermi-LAT data in conjunction with the 10-year point source catalogue. Where a gamma-ray excess…