Related papers: Cosmic Ray Positrons from Cosmic Strings
We investigate the observed spectrum of cosmic-ray electrons and positrons from astrophysical sources, especially pulsars, and the physical processes for making the spectrum spiky or smooth via continuous and multiple electron/positron…
Cosmic strings are linear concentrations of energy that form whenever phase transitions in the early universe break axial symmetries as originally shown by Kibble. They are the result of frustrated order in the quantum fields responsible…
This review concentrates on the results obtained, over the last ten years, on the astrophysics of high-energy cosmic ray electrons and positrons. The anomalies, observed in the data of recent experiments (possible bump in the electron…
Gravitational and massless particle radiation of straight cosmic strings with finite thickness is studied analytically. It is found that the non-linear interaction of the radiation fields emitted by a cosmic string with the ones of the…
The positron fraction in cosmic rays was found to be a steadily increasing in function of energy, above $\sim$ 10 GeV. This behaviour contradicts standard astrophysical mechanisms, in which positrons are secondary particles, produced in the…
In a previous paper the spectrum of positrons produced by matter initially at rest falling onto a massive compact object was calculated. In this paper this calculation is generalized to obtain both the spectrum of in-flight positron…
Most cosmic ray particles observed derive from the explosions of massive stars, which commonly produce stellar black holes in their supernova explosions. When two such black holes find themselves in a tight binary system they finally merge…
Cosmological evolution of axionic strings is investigated by numerically solving field equations of a complex scalar field in 3+1 dimensions. It is shown that the global strings relax to the scaling solution with a significantly smaller…
Brane inflation in superstring theory predicts that cosmic strings (but not domain walls or monopoles) are produced towards the end of the inflationary epoch. Here, we discuss the production, the spectrum and the evolution of such cosmic…
Cosmic strings, a hot subject in the 1980's and early 1990's, lost its appeal when it was found that it leads to inconsistencies in the power spectrum of the measured cosmic microwave background temperature anisotropies. However,…
Thermalized fireballs should be created by cusp events on superconducting cosmic strings. This simple notion allows to reliably estimate particle emission from the cusps in a given background magnetic field. With plausible assumptions about…
We develop a theory to account for the cosmic ray spectrum between 1 GeV and 10^4 GeV following the earlier papers of this series. We use the basic concept that the cosmic ray particles are accelerated in a supernova shock that travels…
AMS instrument aboard the International Space Station is a high precision instrument capable of collecting large statistics on cosmic ray intensities and as such has started making highly significant contributions to Astroparticle Physics.…
The spectrum of cosmic ray protons and electrons released by supernova remnants throughout their evolution is poorly known, because of the difficulty in accounting for particle escape and confinement in the downstream of a shock front,…
Positron and electron cosmic rays provide a complementary way to study the galactic environment. The actual cosmic rays experiments, for instance PAMELA and HEAT, have presented very exciting results in this field. The observed positron…
The IceCube experiment recently detected the first flux of high-energy neutrinos in excess of atmospheric backgrounds. We examine whether these neutrinos originate from within the same extragalactic sources as ultrahigh-energy cosmic rays.…
Cosmic strings are one-dimensional topological defects which could have been formed in the early stages of our Universe. They triggered a lot of interest, mainly for their cosmological implications: they could offer an alternative to…
The field of ultra-high energy cosmic rays made a lot of progresses last years with large area experiments such as the Pierre Auger Observatory, HiRes and the Telescope Array. A suppression of the cosmic ray flux at energies above…
We analyze all individual cosmic strings of various lengths in a large ensemble of the global cosmic string networks in the post-inflationary scenario, obtained from numerical simulations on a discrete lattice with $N^3 = 4096^3$. A strong…
We report that axions and photons exhibit instability in the presence of cosmic strings that are carrying magnetic flux in their core. The strength of the instability is determined by the symmetry breaking scale of the cosmic string theory.…