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Related papers: Fermi Pulsars and the Cosmic Ray Knee

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A consistent theory is developed of the volume energy oscillations of spherical nuclei due to sharpness of the Fermi distribution boundary for quasiparticles. The lowest value of the oscillating part of the energy corresponds to a magic…

Nuclear Theory · Physics 2007-05-23 V. G. Nosov , A. M. Kamchatnov

The question of the origin of ultra-high-energy cosmic rays at relativistic shock waves is discussed in the light of results of recent Monte Carlo studies of the first-order Fermi particle acceleration (Niemiec & Ostrowski 2006, Niemiec et…

Astrophysics · Physics 2007-05-31 Jacek Niemiec , Michal Ostrowski , Martin Pohl

In the common model supernova shock-acceleration of cosmic rays there are two open questions: 1. where does the high energy cosmic rays below the knee (10$^4-10^6$ Gev) come from, and 2. are cosmic ray accelerated only at their origin or…

Astrophysics · Physics 2007-05-23 Amri Wandel

I develop a theory to account for the cosmic ray spectrum. The essential assumption is that, due to fast convective motions, the free mean path perpendicular to the magnetic field is independent of energy and has the scale of the thickness…

Astrophysics · Physics 2007-05-23 Peter L. Biermann

The process of cosmic ray first-order Fermi acceleration at relativistic shock waves is studied with the method of Monte Carlo simulations. The simulations are based on numerical integration of particle equations of motion in a turbulent…

Astrophysics · Physics 2009-11-10 Jacek Niemiec , Michal Ostrowski

Contribution of nearby pulsars to the cosmic rays observed at Earth has been studied. It is found that the experimental bound on amplitude of cosmic ray anisotropy may produce significant constraint on the efficiency of converting pulsar…

Astrophysics · Physics 2009-11-11 A. Bhadra

Cosmic rays of kinetic energies below ~1 GeV per nucleon are thought to play a key role in the chemistry and dynamics of the interstellar medium. They are also thought to be responsible for nucleosynthesis of the light elements Li, Be, and…

High Energy Astrophysical Phenomena · Physics 2011-09-09 V. Tatischeff , J. Kiener

We propose that the knee in the cosmic ray spectrum at energies E ~ 10^{15.5} eV is due to "new physics", namely to a channel in the high energy (~ TeV in the CM) proton interactions hitherto unaccounted for in estimating the energies of…

Astrophysics · Physics 2007-05-23 D. Kazanas , A. Nicolaidis

An overview on the present observational status and phenomenological understanding of cosmic rays above 10^16 eV is given. Above these energies the cosmic ray flux is expected to be gradually dominated by an extra-galactic component. In…

Astrophysics · Physics 2008-12-16 Michael Unger

The Galactic cosmic ray spectrum is a remarkably straight power law. Our current understanding is that the dominant sources that accelerate cosmic rays up to the knee ($3 \times 10^{15}$ eV) or perhaps even the ankle ($3 \times 10^{18}$…

High Energy Astrophysical Phenomena · Physics 2015-06-17 K. M. Schure , A. R. Bell

A year after \emph{Fermi} was launched, the number of known gamma-ray pulsars has increased dramatically. For the first time, a sizable population of pulsars has been discovered in gamma-ray data alone. For the first time, millisecond…

High Energy Astrophysical Phenomena · Physics 2009-12-21 L. Guillemot , Fermi LAT Collaboration

The energy at which cosmic rays from extra-galactic sources begin to dominate over those from galactic sources is an important open question in astroparticle physics. A natural candidate is the energy at the 'ankle' in the approximately…

High Energy Astrophysical Phenomena · Physics 2014-11-18 Markus Ahlers , Luis A. Anchordoqui , Subir Sarkar

We study the survival of ultrahigh energy nuclei injected in clusters of galaxies, as well as their secondary neutrino and photon emissions, using a complete numerical propagation method and a realistic modeling of the magnetic, baryonic…

High Energy Astrophysical Phenomena · Physics 2010-02-23 K. Kotera , D. Allard , K. Murase , J. Aoi , Y. Dubois , T. Pierog , S. Nagataki

Nuclear Coulomb potential at completely ionized and extremely thin atmosphere can leaks to a macroscopic spatial scale. This effect is used to explain the difference between the energy spectra of cosmic-ray electrons around $1 TeV$ measured…

High Energy Astrophysical Phenomena · Physics 2019-09-12 Wei Zhu , Jianhong Ruan , Peng Liu , Lei Feng , Fan Wang

The coupling of photons with (ultra-) relativistic atomic nuclei is presented in two particular circumstances: very high electromagnetic fields and very short photon pulses. We consider a typical situation where the (bare) nuclei (fully…

Nuclear Theory · Physics 2013-12-05 M. Apostol , M. Ganciu

The origin of cosmic rays at all energies is still uncertain. In this paper we present and explore an astrophysical scenario to produce cosmic rays with energy ranging from below $10^{15}$ o $3 \times 10^{20}$ eV. We show here that just our…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Peter L. Biermann , Vitor de Souza

What is the meaning of the Fermi Paradox -- are we alone or is starfaring rare? Can general relativity be united with quantum mechanics? The searches for answers to these questions could intersect. It is known that an accelerator capable of…

High Energy Astrophysical Phenomena · Physics 2015-03-06 Brian C. Lacki

Some general features of cosmic ray acceleration are summarized along with some inferences that can be drawn concerning the origin of the UHE component. The UHE luminosity density is found to be similar to that derived for GeV cosmic rays…

Astrophysics · Physics 2010-12-03 R. D. Blandford

Most cosmic rays are thought to be accelerated by the shocks of supernova explosions of very massive stars. Here we review one quantitative proposal, which predicted the spectral slopes, bend and cutoff about the cosmic ray spectrum across…

Astrophysics · Physics 2009-11-10 Peter L. Biermann

The understanding of the particle spectra resulting from acceleration in relativistic shocks as they occur in extragalactic sources, is essential for the interpretation of the cosmic ray spectrum above the ankle ($E_p>3\cdot 10^{18}$ eV).…

Astrophysics · Physics 2007-08-13 A. Meli , J. Becker , J. J. Quenby , J. Luenemann
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