相关论文: Ultrahigh Energy Cosmic Rays and Neutrinos
I discuss recent advances being made in the physics and astrophysics of cosmic rays and cosmic gamma-rays at the highest observed energies as well as the related physics and astrophysics of very high energy cosmic neutrinos. I also discuss…
The IceCube collaboration reports a detection of extra-terrestrial neutrinos. The isotropy and flavor content of the signal, and the coincidence, within current uncertainties, of the 50 TeV to 2 PeV flux and the spectrum with the…
Scientific motivations for ultra- and extremely high energy neutrino astronomy are considered. Sources and expected fluxes of EHE/UHE neutrinos are briefly discussed. Operating and planned experiments on astrophysical neutrino detection are…
The observation of twenty cosmic-ray air-showers at and above 10^{20} eV poses fascinating problems for particle astrophysics: how the primary particles are accelerated to these energies, how the primaries get here through the 2.7K…
We present a brief introduction to the physics of Ultra High Energy Cosmic Rays (UHECRs), concentrating on the experimental results obtained so far and on what, from these results, can be inferred about the sources of UHECRs.
Understanding the origins of ultrahigh energy cosmic rays (UHECRs) - which reach energies in excess of $10^{20}~{\rm eV}$ - stretches particle acceleration physics to its very limits. In this review, we discuss how such energies can be…
We calculate the flux of neutrinos generated by the propagation of ultra-high energy nuclei over cosmological distances. The propagation takes into account the interactions with cosmic background radiations including the CMB and the most…
The origin of the particles in the highest energy end of the cosmic ray spectrum is discussed in the context of the wider problem of the origin of the whole cosmic radiation as observed at the Earth. In particular we focus our attention on…
Cosmic ray astronomy attempts to identify and study the sources of ultrahigh energy cosmic rays. It is unique in its reliance on charged particles as the information carriers. While no discrete source of ultrahigh energy cosmic rays has…
The $\gamma$-ray emission observed in several classes of Galactic and extragalactic astrophysical sources appears to be linked to accreting black holes and rotational powered neutron stars. These systems are prodigious cosmic accelerators,…
The current status of the ultrahigh energy cosmic ray (UHE CR) enigma and several proposed solutions involving particle physics beyond the standard model are discussed. Emphasis is given to top--down models, and as a main example,…
Diffuse background of high energy neutrinos arising from interactions of cosmic ray protons with far infrared radiation background in extragalactic space is calculated. It is assumed that cosmic ray spectrum at superhigh energies has…
The detection of cosmic rays with energy around and in excess of $10^{20}$ eV raises many questions that future experiments will help answering to. I address here my view of some of these open issues, as they are now and as they might be…
While propagating from their source to the observer, ultrahigh energy cosmic rays interact with cosmological photon backgrounds and generate to the so-called "cosmogenic neutrinos". Here we study the parameter space of the cosmogenic…
The possibility that the observed Ultra High Energy Cosmic Rays are generated by high energy neutrinos creating "Z-bursts" in resonant interactions with the background neutrinos has been proposed, but there are difficulties in generating…
Galactic cosmic rays reach energies of at least several PeV, and their interactions should generate $\gamma$-rays and neutrinos from decay of secondary pions. Therefore, Galactic sources have a guaranteed contribution to the total…
The luminosity densities of high-energy cosmic radiations are studied to find connections among the various components, including high-energy neutrinos measured with IceCube and gamma rays with the Fermi satellite. Matching the cosmic-ray…
In this review paper, we present the main aspects of high-energy cosmic neutrino astrophysics. We begin by describing the generic expectations for cosmic neutrinos, including the effects of propagation from their sources to the detectors.…
Production of the expected high energy neutrino flux with energy greater than tens of thousands of GeV in some astrophysical sites such as the galactic plane as well as the centers of some distant galaxies is reviewed. The expected changes…
We explore scenarios where the highest energy cosmic rays are produced by new particle physics near the grand unification scale. Using detailed numerical simulations of extragalactic nucleon, gamma-ray, and neutrino propagation, we show the…