An improved model for cosmic-ray propagation.
Cosmic ray propagation Jokipii model modification, taking into account particle mirroring to determine diffusion coefficient by limited portion of field spectrum
Noerdlinger, P. D.↗
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Cosmic-ray propagation.
Cosmic ray propagation, discussing interstellar matter effect on composition and diffusion effect necessary to study radiation models
Fichtel, C. E.↗
Discrete sources and the statistics of cosmic- ray propagation
Cosmic ray diffusion from discrete sources in random galactic location, studying chemical constituents anisotropy and age with scattering model
Ramaty, R.↗
Solar cosmic ray propagation characteristics.
Solar cosmic ray propagation and adequacy of current models to explain modes of propagation
COSMIC RAY PROPAGATION↗
Cosmic-ray propagation processes. III.
Cosmic ray propagation processes studied from measurement of anisotropic character of cosmic radiation /1965-1966/
DIURNAL VARIATION↗
A simulation of high energy cosmic ray propagation 2
The cosmic ray propagation in the Galactic arm is simulated. The Galactic magnetic fields are known to go along with so called Galactic arms as a main structure with turbulences of the scale about 30pc. The distribution of cosmic ray in Galactic arm is studied. The escape time and the possible anisotropies caused by the arm structure are discussed.
Honda, M.↗
An improved model for cosmic ray propagation
Model for cosmic ray propagation with particle mirroring
Noerdlinger, P. D.↗
A simulation of high energy cosmic ray propagation 1
High energy cosmic ray propagation of the energy region 10 to the 14.5 power - 10 to the 18th power eV is simulated in the inter steller circumstances. In conclusion, the diffusion process by turbulent magnetic fields is classified into several regions by ratio of the gyro-radius and the scale of turbulence. When the ratio becomes larger then 10 to the minus 0.5 power, the analysis with the assumption of point scattering can be applied with the mean free path E sup 2. However, when the ratio is smaller than 10 to the minus 0.5 power, we need a more complicated analysis or simulation. Assuming the turbulence scale of magnetic fields of the Galaxy is 10-30pc and the mean magnetic field strength is 3 micro gauss, the energy of cosmic ray with that gyro-radius is about 10 to the 16.5 power eV.
Honda, M.↗
Cosmic-ray propagation and containment
The cosmic rays are an active gaseous component of the disk of the galaxy, and their propagation and containment is a part of the general dynamics of the disk. The sources of cosmic rays are a matter of speculation. The disk is inflated by the cosmic-ray gas pressure, P, comparable to the magnetic pressure B super 2/ 8 pi, but the rate of inflation is unknown. The time spent by the individual cosmic-ray particles in the disk is inversely proportional to the cosmic-ray production rate and may be anything from 100,000 to more than 10 million years. It is evident from the decay of Be(10) that the cosmic rays circulate through a volume of space perhaps ten times the thickness of the gaseous disk, suggesting a magnetic halo extending out approximately 1 kpc from either face of the disk. The cosmic rays may be responsible for the halo by inflating the magnetic fields of the disk. Extension of the fields to 1 kpc would imply a high production rate and short life of cosmic rays in the dense gaseous disk of the galaxy.
Parker, E. N.↗
Cosmic ray propagation and containment
The cosmic rays, an active gaseous component of the disk of the galaxy, are considered along with their propagation and containment as a part of the general dynamics of the disk. The sources of cosmic rays are a matter of speculation. The disk is inflated by the cosmic ray gas pressure comparable to the magnetic pressure, but the rate of inflation is unknown. The time spent by the individual cosmic ray particles in the disk is inversely proportional to the cosmic ray production rate. It is evident from the decay of Be(1c) that the cosmic rays circulate through a volume of space perhaps ten times the thickness of the gaseous disk, suggesting a magnetic halo extending out approximately 1 kpc from either face of the disk. The cosmic rays may be responsible for the halo by inflating the magnetic fields of the disk. Extension of the fields to 1 kpc would imply a high production rate and short life of cosmic rays in the dense gaseous disk of the galaxy.
Parker, E. N.↗
A formalism for cosmic ray propagation studies
The continuity equation for cosmic ray propagation is used to derive a set of linear equations interrelating the fluxes of multiply charged nuclei as observed at any particular part of the galaxy. The derivation leads to model independent definitions for cosmic ray storage time, mean density of target nuclei and effective mass traversed. The set of equations form a common framework for comparisons of theories and observations. As an illustration, it is shown that there exists a large class of propagation models which give the same result as the exponential path length model. The formalism is shown to accommodate dynamic as well as equilibrium models of production and propagation.
Golden, R. L.↗
Local superbubble model of cosmic ray propagation
The consequences for cosmic ray phenomena of the solar system being inside a superbubble are explored. The superbubble is found to expand with time, thus causing the contained relativistic cosmic rays to lose energy. The local superbubble model offers a natural explanation for features in the high energy cosmic ray anisotropy and spectrum which occur around 10 to the 15th eV and which are due to failure of the superbubble wall to contain cosmic rays of high energy. In the energy range from 3 x 10 to the 14th eV to 10 to the 17th eV, the direction of the measured anisotropy indicates a net local flow from the nearby wall, whereas above 10 to the 17th eV the anisotropy direction is reversed, indicating a return to net outward flow of cosmic rays toward the local wall.
Streitmatter, R. E.↗
The energy dependence of cosmic ray propagation at low energy
The interstellar propagation of cosmic rays is investigated using current 'best estimates' for the partial and total cross sections and their energy dependence and the current model of solar modulation. The experimental boron to carbon ratio is reproduced if the mean of the path length distribution decreases with decreasing energy below approximately 1 GeV/nucleon. This energy dependence is compared to shock acceleration models and dynamical halo models using different galactic wind velocities.
Garcia-Munoz, M.↗
Two views of cosmic ray propagation in the solar system
Diffusion and scatter free cosmic ray propagation theories are discussed in terms of the quality of their alternate viewpoints. A hypothetical model of conditions in interplantary space is described which aids in the comparison. A plot of the intensity of the interplanetary magnetic field over a long period is presented, and the association of these regions with high velocity streams is shown to support the scatter free viewpoint.
Barouch, E.↗
The ultraheavy cosmic rays - Propagation and selective acceleration
Results of calculations of ultraheavy cosmic ray propagation are examined in the light of recent observations and theoretical advances with the objective of distinguishing the effects of propagation from nucleosynthesis and preferential acceleration. The results presented here have been calculated by the method described in Margolis (1983), with elements from iron (Z = 26) to uranium (Z = 92) combined in a single calculation. The source abundances of Anders and Ebihara (1982) have been used as a reference composition. It is shown, in particular, that the relative abundances of Sr and Ba are substantially increased by using the modified ionization potential dependence (MIPD) compared with solar abundances and the first ionization potential dependence (FIPD) model. In contrast, Pb shows similar enhancements in both FIPD and MIPD models.
Margolis, S. H.↗
The physical theory of one dimensional galactic cosmic-ray propagation in the atmosphere
An analytical theory of atmospheric cosmic-ray propagation is developed based on a phenomenological model of hadron-nucleus collisions. This model correctly predicts the sea level cosmic-ray nucleon, pion and muon spectra, the cosmic-ray ionization profile in the atmosphere, and neutron flux and density profiles in the atmosphere. It is concluded that the large scale properties of atmospheric cosmic-rays can be accurately predicted on the basis of a nucleonic cascade with all secondaries mediated by pion production. Implications for energy independence of cross sections, the recent 70 GeV results from Serpukhov, and nucleonic relaxation rates in the atmosphere are discussed.
Obrien, K.↗
Constraints on cosmic ray propagation in the galaxy
The goal was to derive a more detailed picture of magnetohydrodynamic turbulence in the interstellar medium and its effects on cosmic ray propagation. To do so, radio astronomical observations (scattering and Faraday rotation) were combined with knowledge of solar system spacecraft observations of MHD turbulence, simulations of wave propagation, and modeling of the galactic distribution to improve the knowledge. A more sophisticated model was developed for the galactic distribution of electron density turbulence. Faraday rotation measure data was analyzed to constrain magnetic field fluctuations in the ISM. VLBI observations were acquired of compact sources behind the supernova remnant CTA1. Simple calculations were made about the energies of the turbulence assuming a direct link between electron density and magnetic field variations. A simulation is outlined of cosmic ray propagation through the galaxy using the above results.
Cordes, James M.↗