Related papers: Spallogenic Light Elements and Cosmic-Ray Origin
The Earth is continuously showered by charged cosmic ray particles, naturally produced atomic nuclei moving with velocity close to the speed of light. Among these are ultra high energy cosmic ray particles with energy exceeding 5x10^19 eV,…
The origin of cosmic rays is one of the major unresolved astrophysical questions. In particular, the highest energy cosmic rays observed possess macroscopic energies and their origin is likely to be associated with the most energetic…
We discuss the prospects of detecting the sources of ultra-high energy (UHE) cosmic ray (CR) nuclei via their emission of cosmogenic gamma-rays in the GeV to TeV energy range. These gamma-rays result from electromagnetic cascades initiated…
We present COSMOCR, a numerical code for the investigation of cosmic ray related studies in computational cosmology. The code follows the diffusive shock acceleration, the mechanical and radiative energy losses and the spatial transport of…
While SNRs have been considered the most relevant Galactic CR accelerators for decades, CCSNe could accelerate particles during the earliest stages of their evolution and hence contribute to the CR energy budget in the Galaxy. Some SNRs…
We examine the question of the origin of the Galactic cosmic-rays (GCRs) in the light of the data available at the highest energy end of the spectrum. We argue that the data of the Pierre Auger Observatory and of the KASCADE-Grande…
The much-anticipated proof of cosmic ray (CR) acceleration in supernova remnants (SNR) must hinge on full consistency of acceleration theory with the observations; direct proof is impossible because of the orbit scrambling of CR particles.…
The identification of Cosmic Ray (CR) sources represents one of the biggest and long-standing questions in astrophysics. Direct measurements of cosmic rays cannot provide directional information due to their deflection in (extra)galactic…
We discuss a scenario in which the highest energy cosmic rays (CR's) and cosmological $\gamma$-ray bursts (GRB's) have a common origin. This scenario is consistent with the observed CR flux above $10^{20}\text{eV}$, provided that each burst…
Observations of cosmic rays have been improving at all energies, with higher statistics and reduced systematics. Fundamental questions remain regarding the origins of cosmic rays both within the Galaxy and in extragalactic sources, and new…
Supernova remnants have long been regarded as sources of the Galactic cosmic rays up to petaelectronvolts, but convincing evidence is still lacking. In this work we explore the common origin of the subtle features of the cosmic ray spectra,…
Supernova remnants are known to accelerate cosmic rays (CRs) on account of their non-thermal emission of radio waves, X-rays, and gamma rays. However, the ability to accelerate CRs up to PeV-energies has yet to be demonstrated. The presence…
Precise measurements of the energy spectra of cosmic rays (CRs) show various kinds of features deviating from single power-laws, which give very interesting and important implications on their origin and propagation. Previous measurements…
Cosmic rays (CRs) are known to play a key role in many astrophysical environments: they can modify shock dynamics, influence the thermochemistry and the ionization of the interstellar medium, regulate galaxy mass content by driving galactic…
The origin and nature of the ultrahigh energy cosmic rays remains a mystery. However, considerable progress has been achieved in past years due to observations performed by the Pierre Auger Observatory and Telescope Array. Above $10^{18}$…
Galactic cosmic rays (CRs) are accelerated at the forward shocks of supernova remnants (SNRs) via diffusive shock acceleration (DSA), an efficient acceleration mechanism that predicts power-law energy distributions of CRs. However,…
The extended jet structures of radio galaxies (RGs) represent an ideal acceleration site for High Energy Cosmic Rays (HECRs) and a recent model showed that the HECR data can be explained by these sources, if the arrival directions of HECRs…
We investigate the impact of cosmic rays (CRs) on galactic outflows from a multi-phase interstellar medium with solar neighbourhood conditions. The three-dimensional magneto-hydrodynamical simulations include CRs as a relativistic fluid in…
We have measured the isotopic abundances of neon and a number of other species in the galactic cosmic rays (GCRs) using the Cosmic Ray Isotope Spectrometer (CRIS) aboard the ACE spacecraft. Our data are compared to recent results from…
With the newest version of our Monte Carlo code for ultra-high-energy cosmic ray (UHECR) propagation, CRPropa 3, the flux of neutrinos and photons due to interactions of UHECRs with extragalactic background light can be predicted. Together…