Related papers: Spallogenic Light Elements and Cosmic-Ray Origin
The acceleration of cosmic ray particles and their propagation in the Milky Way and the heliosphere tangle with each other, leading to complexity and degeneracy of the modeling of Galactic cosmic rays (GCRs). The recent measurements of the…
A short overview is presented of current issues concerning the production and evolution of Li, Be and B in the Milky Way. It is argued that the currently popular idea that Galactic cosmic rays are accelerated inside metal-rich superbubbles…
The light elements, Li, Be, and B, provide tracers for many aspects of astronomy including stellar structure, Galactic evolution, and cosmology. We have taken spectra of Be in 117 metal-poor stars ranging in metallicity from [Fe/H] = -0.5…
Galaxy formation simulations demonstrate that cosmic-ray (CR) feedback may be important in the launching of galactic-scale winds. CR protons dominate the bulk of the CR population, yet most observational constraints of CR feedback come from…
Energetic gamma rays (GeV to TeV photon energy) have been detected toward several supernova remnants (SNR) associated with molecular clouds. If the gamma rays are produced mainly by hadronic processes rather than leptonic processes like…
Data obtained in the ATIC-2 (Advanced Thin Ionization Calorimeter), CREAM (Cosmic Ray Energetics and Mass)) and PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) experiments suggest that elemental interstellar…
Cosmic rays are mostly composed of protons accelerated to relativistic speeds. When those protons encounter interstellar material, they produce neutral pions which in turn decay into gamma rays. This offers a compelling way to identify the…
It is well known that cosmic rays (CRs) contribute significantly to the pressure of the interstellar medium in our own Galaxy, suggesting that they may play an important role in regulating star formation during the formation and evolution…
The X-ray synchrotron emission of each of the young supernova-remnants (SNRs) SN1006, Kepler, Tycho, RCW86 and Cas A, is roughly given by $\nu L_{\nu}\sim 10^{45}\rm{erg}/t$, where $t$ is the remnant's age. The electrons emitting the X-ray…
The accurate determination of the elemental composition of cosmic rays at high energies is expected to provide crucial clues on the origin of these particles. Previous direct measurements of composition have been limited by experiment…
Precise measurements of galactic cosmic rays revealed a significant difference between the rigidity spectral indices of protons and helium ions. This finding is a notable contrast to the commonly accepted theoretical prediction that…
Galactic cosmic ray (CR) acceleration to the knee in the spectrum at a few PeV is only possible if the magnetic field ahead of a supernova remnant (SNR) shock is strongly amplified by CR escaping the SNR. A model formulated in terms of the…
Until now, providing an experimental unambiguous proof of Cosmic Ray (CR) origin has been elusive. The SuperNova Remnant (SNR) study showed an increasingly complex scenario with a continuous elaboration of theoretical models. The…
The origin of ultra-high energy cosmic rays $($UHECRs$)$ remains a mystery. It has been suggested that UHECRs can be produced by the stochastic acceleration in relativistic jets of gamma-ray bursts $($GRBs$)$ at the early afterglow phase.…
Cosmic Rays (CR) impinging on the terrestrial atmosphere provide a viable opportunity to study new physics in hadron-nucleus collisions at energies covering many orders of magnitude, including a regime well beyond LHC energies. The…
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…
Since its launch, the Alpha Magnetic Spectrometer-02 (AMS-02) has delivered outstanding quality measurements of the spectra of cosmic-ray (CR) species, $\bar{p}$, $e^{\pm}$, and nuclei (H-Si, Fe), which resulted in a number of…
The presence of short-lived radionuclides in the early solar system provides important information about the astrophysical environment in which the solar system formed. The discovery of now extinct $^{10}$Be in calcium-aluminum-rich…
The search for a theory of the origin of cosmic rays that may be considered as a standard, agreeable model is still ongoing. On one hand, much circumstantial evidence exists of the fact that supernovae in our Galaxy play a crucial role in…
Using recent measurements of the spectrum and chemical composition of the highest energy cosmic rays, we consider the sources of these particles. We find that the data strongly prefers models in which the sources of the ultra-high energy…