Origin of primary cosmic radiation and its antiproton component.
Primary cosmic ray origin and acceleration and antiproton energy spectrum, using Fokker-Planck diffusion equation
Bowen, T.↗
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Cosmic Ray Origin, Acceleration and Propagation
This paper summarizes highlights of the OG3.1, 3.2 and 3.3 sessions of the 26th International Cosmic Ray Conference in Salt Lake City, which were devoted to issues of origin/composition, acceleration and propagation.
Baring, Matthew G.↗
Timed Collections in the NASA Cosmic Dust Aircraft Collected Particle Collection Including Previous Collectors
The NASA Cosmic Dust Collections includes a collection of interplanetary particles gathered using high-altitude aircraft (the Aircraft Collected Particle collection, or ACP). These particles include cosmic-origin particles as well as particles of terrestrial origin such as volcanic ash, solid rocket motor effluent, and terrestrial dust. The cosmic-origin dust comes from two principal sources - material originating from the diffuse interplanetary background which are uncoupled from the orbits of larger bodies, and cometary-origin particles which are dynamically coupled with the orbits of their parent bodies to form dust streams. These dust stream particles generate short-lived, annual meteor showers and are important because, if they can be identified as originating from a given dust stream, they can be studied in the laboratory as samples of a specific comet. Collecting these particles requires dedicated ACP flights which are timed to coincide with a specific meteor shower. These “timed collections” hold the promise of providing samples from a suite of comets including those never visited by spacecraft [1-3]. This abstract describes a recent (Dec 2020) timed collection attempt, lists previous timed collections with collected particles available for request from the NASA Cosmic Dust Collections, as well as listing ACP collectors which were collected when no meteor showers were active for potential use as control samples.
cosmic dust↗
Energy Spectrum and Mass Composition of Ultra-high-energy Cosmic Rays Originating from Relativistic Jets of Nearby Radio Galaxies
Relativistic jets of radio galaxies (RGs) are possible sources of ultra-high-energy cosmic rays (UHECRs). Recent studies combining relativistic hydrodynamic simulations with Monte Carlo particle transport have demonstrated that UHECRs can be accelerated to energies beyond 10 20 eV through shocks, turbulence, and relativistic shear in jet-induced flows of Fanaroff–Riley type RGs. The resulting time-asymptotic UHECR spectrum is well modeled by a double power law with an “extended” exponential cutoff, primarily shaped by relativistic shear acceleration. In this study, we adopt this novel source spectrum and simulate the propagation of UHECRs from nearby RGs using the CRPropa code. We focus on Virgo A (Vir A), Centaurus A (Cen A), Fornax A (For A), and Cygnus A (Cyg A), expected to be the most prominent UHECR sources among RGs. We then analyze the energy spectrum and mass composition of UHECRs arriving at Earth. We find that, due to the extended high-energy tail in the source spectrum, UHECRs from Vir A, which has a higher Lorentz factor, exhibit a higher flux at the highest energies and a lighter mass composition at Earth compared to those from Cen A and For A with lower Lorentz factors. Despite Cyg A having an even higher Lorentz factor, the large distance limits its contribution. With a small number of nearby prominent RGs, our findings suggest that if RGs are the major sources of UHECRs, the energy spectrum and mass composition of observed UHECRs would exhibit hemispheric differences between the Northern and Southern skies at the highest energies.
79 ASTRONOMY AND ASTROPHYSICS↗
On galactic origin of cosmic rays with energy up to 10(19) eV
The experimental data on ultrahigh energy cosmic ray anisotropy are considered. In supposed models of galactic magnetic field the main characteristics of expected anisotropy are estimated and are compared with the experimental data. It is shown that particles with energy up to 10 to the 19th power eV are of galactic origin.
Efimov, N. N.↗
Origin of cosmic magnetic fields
Reasons for describing cosmic hydromagnetic phenomena by introducing electric currents are summarized demonstrating that change from the traditional magnetic field description to a current description provides new aspects of cosmic electrodynamics. It is shown that the kink-instability of electric currents is the basic physical phenomenon responsible for magnetic flux generation in cosmic physics. A model which starts with a poloidal magnetic field is discussed; differential motions change the field configuration so that kinetic energy is transferred into magnetic energy of induced toroidal fields; the currents associated with these become unstable when the toroidal energy exceeds the poloidal energy resulting in an amplification of the original poloidal field.
Alfven, H.↗
New Results from Fermi-LAT and Their Implications for the Nature of Dark Matter and the Origin of Cosmic Rays
The measured spectrum is compatible with a power law within our current systematic errors. The spectral index (-3.04) is harder than expected from previous experiments and simple theoretical considerations. "Pre-Fermi" diffusive model requires a harder electron injection spectrum (by 0.12) to fit the Fermi data, but inconsistent with positron excess reported by Pamela if it extends to higher energy. Additional component of electron flux from local source(s) may solve the problem; its origin, astrophysical or exotic, is still unclear. Valuable contribution to the calculation of IC component of diffuse gamma radiation.
Moiseev, Alexander↗
Life's origin: the cosmic, planetary and biological processes
From elements formed in interstellar furnaces to humans peering back at the stars, the evolution of life has been a long, intricate and perhaps inevitable process. Life as we know it requires a planet orbiting a star at just the right distance so that water can exist in liquid form. It needs a rich supply of chemicals and energy sources. On Earth, the combination of chemistry and energy generated molecules that evolved ways of replicating themselves and of passing information from one generation to the next. Thus, the thread of life began. This chart traces the thread, maintained by DNA molecules for much of its history, as it weaves its way through the primitive oceans, gaining strength and diversity along the way. Organisms eventually moved onto the land, where advanced forms, including humans, ultimately arose. Finally, assisted by a technology of its own making, life has reached back out into space to understand its own origins, to expand into new realms, and to seek other living threads in the cosmos.
NASA Center ARC↗
On the origin of cosmic rays proiskhozhdenii kosmicheskikh luchey
Explore the source record for details and available documents.
Ginzburg, V. L.↗
Origin of cosmic X rays.
X-ray astronomy emphasizing interpretation of observational results and relationship to radio and optical astronomy and cosmic ray physics
RADIO ASTRONOMY↗
Experimental tests of the supernovae origin of cosmic rays
Detection of supernovae pulse by gamma ray telescope and atmospheric scintillation method
Fichtel, C. E.↗
Origin of cosmic rays
A model is presented in which cosmic electrons are produced by pulsars, and cosmic protons and alpha particles are accelerated by shock waves in supernova envelopes. It is argued that neither mechanism by itself can produce both the observed protons and electrons at energies above a few hundred MeV. But supernova accelerated electrons could constitute the majority of cosmic electrons with energy below about 10 MeV.
Cohen, J. M.↗
On the origin of cosmic rays
Using Recent surveys of molecular clouds and gamma rays in the galaxy, it is possible to determine the distribution of 1 to 10 GeV cosmic-ray nucleons in the galaxy. This distribution appears to be identical to the supernova remnant distribution to within experimental error and provides strong support for the hypothesis that supernovae produce most of the observed cosmic rays. This distribution resembles that of OB associations of average age approximately 30 million years suggesting that cosmic rays are produced by population objects about 30 million years after their birth.
Stecker, F. W.↗
Origin of cosmic rays
Based on recent observations of the galactic gas and gamma ray distributions, the galactic cosmic ray distribution is deduced. This distribution is identical to that of supernova remnants (within experimental error), strongly supporting the hypothesis that most observed cosmic rays are produced by supernovas in our own galaxy. The average age of the cosmic ray sources is suggested, from the character of their distribution, to be about 30 million years.
Stecker, F. W.↗
On the origin of cosmic rays
Using recent surveys of molecular clouds and gamma-rays in the galaxy, it has become possible to determine the distribution of 1 to 10 GeV cosmic-ray nucleons in the galaxy. This distribution appears to be identical to the supernova remnant distribution to within experimental error, providing strong support for the hypothesis that supernovae produce most of the observed cosmic rays. This distribution resembles that of OB associations of an average age of 30 million years, suggesting that cosmic rays are produced by population I objects about 30 million years after their birth.
Stecker, F. W.↗
Gamma-ray astronomy and the origin of cosmic rays
New surveys of galactic gamma ray emission together with millimeter wave radio surveys indicated that cosmic rays were produced as the result of supernova explosions in our galaxy with the most intense production occurring in a Great Galactic Ring about 35,000 light years in diameter where supernova remnants and pulsars were concentrated.
Stecker, F. W.↗