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Observatory Detects Extragalactic Cosmic Rays Hitting The Earth（图）
Observatory Detects Extragalactic Cosmic Rays Hitting Earth
2017/10/24
Fifty years ago, scientists discovered that the Earth is occasionally hit by cosmic rays of enormous energies. Since then, they have argued about the source of those ultra-high-energy cosmic rays—whet...
Study Confirms Cosmic Rays Have Extragalactic Origins（图）
Cosmic Rays Extragalactic Origins
2017/10/24
In an article to be published Sept. 22 in the journal Science, a group of more than 400 scientists from 18 nations describe how they detected an anisotropy, an asymmetry in the cosmic particles’ distr...
Help astronomers find elusive muons disguised as gamma rays
astronomers muons disguised gamma rays
2017/3/30
A new citizen science project, led by astronomers at the University of Minnesota, is asking for help from the public to identify and categorize hundreds of thousands of ring patterns within images pro...
Physicists Leapfrog Accelerators with Ultrahigh Energy Cosmic Rays
Physicists Accelerators Ultrahigh Energy Cosmic Rays
2016/11/4
An international team of physicists has developed a pioneering approach to using Ultrahigh Energy Cosmic Rays (UHECRs)—the highest energy particles in nature since the Big Bang—to study particle inter...
Galactic center's gamma rays unlikely to originate from dark matter,evidence shows
Galactic center gamma rays dark matter
2016/2/23
Bursts of gamma rays from the center of our galaxy are not likely to be signals of dark matter but rather other astrophysical phenomena such as fast-rotating stars called millisecond pulsars, accordin...
Kneelike structure in the spectrum of the heavy component of cosmic rays observed with KASCADE-Grande
ultra-high energy cosmic rays KASCADE-Grande composition extensive air shower
2011/10/20
We report the observation of a steepening in the cosmic ray energy spectrum of heavy primary particles at about $8 \times 10^{16}$ eV. This structure is also seen in the all-particle energy spectrum, ...
Testing the isotropy of high energy cosmic rays using spherical needlets
Testing isotropy high energy cosmic rays using spherical
2011/10/14
For many decades, ultra-high energy charged particles have been a puzzle for particle physicists and astrophysicists. Nor the sites of production, nor the mechanism responsible for the generation of t...
Constraints on the origin of ultra-high-energy cosmic rays from cosmogenic neutrinos and photons
Astroparticle physics Acceleration of particles Abundances Neutrinos Gamma-rays Relativistic processes
2011/10/11
We study the production of cosmogenic neutrinos and photons during the extragalactic propagation of ultra-high-energy cosmic rays (UHECRs). For a wide range of models in cosmological evolution of sour...
HESS J1858+020 is a TeV gamma-ray source that was reported not to have any clear cataloged counterpart at any wavelength. However, it has been recently proposed that this source is indirectly associat...
We study the change in cosmic-ray pressure, the change in cosmic-ray density, and the level of cosmic-ray induced heating via Alfven-wave damping when cosmic rays move from a hot ionized plasma to a c...
Self-consistent evolution of gas and cosmic rays in Cygnus A and similar FR II classic double radio sources
Self-consistent evolution cosmic rays
2011/1/10
In Cygnus A and other classical FR II double radio sources, powerful opposing jets from the cores of halo-centered galaxies drive out into the surrounding cluster gas, forming hotspots of shocked and ...
A possible approach to three-dimensional cosmic-ray propagation in the Galaxy IV. Electrons and electron-induced gamma-rays
three-dimensional cosmic-ray propagation the Galaxy IV. Electrons
2011/1/11
Based on the diffusion-halo model for cosmic-ray (CR) propagation, including stochastic reacceleration due to collisions with hydromagnetic turbulence, we study the behavior of the electron component ...
Orders of Fermi- and Plasma-Accelerations of Cosmic Rays
Fermi- and Plasma-Accelerations Cosmic Rays
2011/1/11
The generic acceleration model for ultra high energy cosmic rays, which has been introduced in {\tt 1006.5708 [astro-ph.HE]}, suggests various types of electromagnetic interactions between cosmic char...
Acceleration and Particle Field Interactions of Cosmic Rays II: Calculations
Acceleration Particle Field Cosmic Rays II
2011/1/13
Based on the generic acceleration model, which suggests different types of electromagnetic interactions between the cosmic charged particles and the different configurations of the electromagnetic (pl...
Cosmic rays: current status, historical context
Cosmic rays current status historical context
2011/1/13
The ISVHECRI conference series emphasizes the connection between high energy physics and cosmic ray physics--the study of elementary particles and nuclei from accelerators in the lab and from space. I...