Related papers: Positronia' clouds in Universe
Depending on their type, supernova remnants may have ejecta material with high abundance of heavy elements such as carbon or oxygen. In addition, core-collapse supernovae explode in the wind material of their progenitor star that may also…
We have investigated light nuclei pair photoproduction in relativistic heavy ion ultraperipheral collisions. As a first attempt, we employ our previously developed quantum electrodynamics model, which incorporates a wave-packet description…
Muon pairs can be produced in the annihilation of ultra-high energy (UHE, $E \gtrsim 10^{18} \,\mathrm{eV}$) photons with low energy cosmic background radiation in the intergalactic space, giving birth to neutrinos. Although the branching…
Binary neutron star mergers can form short-lived magnetar-like remnants whose magnetically dominated polar towers reach $B\sim10^{15}$--$10^{16}\,\mathrm{G}$, but the microphysical composition of these outflows remains poorly understood.…
We calculate the flux of neutrinos generated by the propagation of ultra-high energy iron over cosmological distances and show that even if ultra-high energy cosmic rays are composed of heavy nuclei, a significant flux of high-energy…
The orbital observatories PAMELA and AMS-02 have detected a significant excess in the cosmic ray (CR) positron flux at energies above several tens of GeV. The measured values exceed those expected in models of secondary origin of positrons…
Heavy quarkonium production in ultra-peripheral nuclear collisions (UPC) is described within the QCD dipole formalism. Realistic quarkonium wave functions in the $Q\bar Q$ rest frame are calculated by solving the Schr\"odinger equation with…
The next generation electron-positron colliders are designed for precision studies of the Standard Model and its extensions, in particular in the Higgs sector. We consider the potential for discovery of composite Higgs models in Higgs pair…
A possible setup for the experimental verification of linear Breit-Wheeler pair creation of electrons and positrons in photon-photon collisions is studied theoretically. It combines highly energetic bremsstrahlung photons, which are assumed…
Due to coherence, there are strong electromagnetic fields of short duration in very peripheral heavy ion collisions. They give rise to photon-photon and photon-nucleus collisions with high flux. Photon-photon and photon-hadron physics at…
High-energy neutrinos, arising from decays of mesons that were produced through the cosmic rays collisions with air nuclei, form unavoidable background noise in the astrophysical neutrino detection problem. The atmospheric neutrino flux…
Gamma-ray bursts are produced by the dissipation of the kinetic energy of a highly relativistic fireball, via the formation of a collisionless shock. When this happens, Ultra High Energy Cosmic Rays up to 10^20 eV are produced. I show in…
Collisions of actinide nuclei form, during very short times of few $10^{-21}$ s, the heaviest ensembles of interacting nucleons available on Earth. Such very heavy ions collisions have been proposed as an alternative way to produce heavy…
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…
We investigate the electron-positron pair cascade taking place in the magnetosphere of a rapidly rotating black hole. Because of the spacetime frame dragging, the Goldreich-Julian charge density changes sign in the vicinity of the event…
A several-step theoretical model is constructed to trace the origin of ultra high energy (UHE) $[1-2]$PeV neutrinos detected, recently, by the IceCube collaboration. Protons in the AGN magnetosphere, experiencing different gravitational…
Gamma ray emission of 511 keV lines arising from electron-positron annihilation has been detected from the Galaxy since the 70s. Spatially resolved observations using the INTEGRAL satellite have shown its full sky distribution to be…
Electron-positron pairs' generation occuring in the interaction of $10^{18}$-$10^{20}$~W/cm$^2$ laser radiation with high-Z targets are examined. Computational results are presented for the pair production and the positron yield from the…
Detecting TeV--PeV cosmic neutrinos provides crucial tests of neutrino physics and astrophysics. The statistics of IceCube and the larger proposed IceCube-Gen2 demand calculations of neutrino-nucleus interactions subdominant to…
The photo-disintegration of cosmic ray nuclei by starlight leads to the production of secondary antineutrinos. We have assumed that the flux of the ultrahigh energy cosmic ray nuclei near the Galactic plane region is the same as that…