Related papers: Structures in the cosmic ray energy spectra
Recent data from ATIC, CREAM and PAMELA indicate that the cosmic ray energy spectra of protons and nuclei exhibit a remarkable hardening at energies above 100 GeV per nucleon. We propose that the hardening is an interstellar propagation…
We present new measurements of the energy spectra of cosmic-ray (CR) nuclei from the second flight of the balloon-borne experiment Cosmic Ray Energetics And Mass (CREAM). The instrument included different particle detectors to provide…
Much has been learned about Galactic cosmic rays in the past decade: On the observational side, the spectra of cosmic ray nuclei have been directly measured with high precision, resolving chemical composition up to TV rigidities. At even…
We introduce neutrino astronomy from the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. Although the discovery of cosmic rays dates back close to a century, we…
The origin of cosmic rays remains an unresolved fundamental problem in astrophysics. The synergy of multiple observational probes, including the energy spectra, the mass composition, and anisotropy is a viable way to jointly uncover this…
The topological defect scenario of origin of the observed highest energy cosmic rays is reviewed. Under a variety of circumstances, topological defects formed in the early Universe can be sources of very massive particles in the Universe…
High energy Astroparticles include Cosmic Ray, gamma ray and neutrinos, all of them coming from the universe. The origin and production, acceleration and propagation mechanisms of ultrahigh-energy CR (up to $10^{20}$ eV) are still unknown.…
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…
In a comprehensive model of Cosmic Rays (CRs) proposed a decade ago, the energies of the spectral "knees" of the various CR species were predicted to be proportional to mass, rather than charge. The model also predicts the knees to occur at…
Extensive air showers still are our only access to the highest-energy particles in the universe, namely cosmic-ray nuclei with energies up to several 100 EeV. Studying open questions in cosmic-ray physics, like their yet unknown origin…
The recent evidence for a cosmological evolution of the fine structure constant \alpha=e^2/\hbar c found from an analysis of absorption systems in the spectra of distant quasars, is modelled by a cosmological scenario in which it is assumed…
Investigations of the origin of cosmic rays are presented. Different methods are discussed: studies of cosmic gamma rays of energy from 30 MeV to about 10^15 eV (since photons point to their places of origin), studies of the mass…
The cosmic ray energy spectra encode very important information about the mechanisms that generate relativistic particles in the Milky Way, and about the properties of the Galaxy that control their propagation. Relativistic electrons and…
The chemical composition of ultra-high energy cosmic rays is a key question in particle astrophysics. The measured composition, inferred from the elongation rates of cosmic ray showers, looks in general very different from the initial…
Cosmic ray (CR) particles arrive at the top of the Earth's atmosphere at a rate of around 1000 per square meter per second. They are mostly ionized nuclei - about 90% protons, 9% alpha particles traces of heavier nuclei and approximately 1%…
Existing small, medium and large arrays for the study of cosmic rays of ultra-high energies are aimed for obtaining information about our galaxy and extragalactic space, namely to search and study astronomical objects that produce the flux…
I discuss and illustrate the development of large-scale structure in the Universe, emphasising in particular the physical processes and cosmological parameters that most influence the observationally accessible aspects of structure at large…
Primary cosmic ray particles above energies of about 100 TeV are investigated by large-area ground based detector installations, observing various components of the development of extensive air-showers (EAS). By such an indirect access to…
Cosmic rays begin to reveal their secrets at energies above 5 EeV. Beyond this characteristic energy, known as the spectral "ankle", the arrival-direction data from the Pierre Auger Observatory show anisotropy on large angular scales of…
Primary energy spectrum of cosmic rays exhibits a knee at about $3$ PeV where a change in the spectral index occurs. Despite many efforts the origin of such a feature of the spectrum is not satisfactorily solved yet. Here it is proposed…