Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Cosmic ray spectrum

The energy spectrum of a nuclear component extends smoothly from about 10 MeV to 10 ° eV (more than 13 decades in energy and 32 decades in intensity). The mean particle energy of the galactic cosmic-ray spectrum is about 1 Gev, and the number density of these particles in interstellar space is about 10" m , almost equal to the... [Pg.15]

The implication of Eq. 17 is that for E1 70 MeV the diffuse gamma-ray spectrum should have the same power law behavior as the proton spectrum, a ss 2.7. What is observed, however, is that the spectrum of gamma-rays from the inner galaxy is harder than this, having a power-law behavior of approximately E 2A (Hunter et al., 1997). This is currently not fully understood. One possibility is that the cosmic-ray spectrum producing the gamma rays is harder than observed locally near Earth (Hunter et al., 1997). [Pg.10]

Figure 5. High-energy cosmic-ray spectrum. References to the data are given in (Gaisser Stanev, 2004). The shaded region indicates a factor of 30 in total energy (see text). Figure 5. High-energy cosmic-ray spectrum. References to the data are given in (Gaisser Stanev, 2004). The shaded region indicates a factor of 30 in total energy (see text).
Figure 9. The ultra-high-energy cosmic-ray spectrum from a paper by Abassi et al., 2002. The points with the fitted curve are from the HiRes fluorescence detectors (Abassi et al., 2004), while the higher set of points are the AGASA spectrum (Takeda et al., 2003). See text for a discussion of the curve. Figure 9. The ultra-high-energy cosmic-ray spectrum from a paper by Abassi et al., 2002. The points with the fitted curve are from the HiRes fluorescence detectors (Abassi et al., 2004), while the higher set of points are the AGASA spectrum (Takeda et al., 2003). See text for a discussion of the curve.
To a first approximation, the all-particle spectrum of cosmic rays can be described by a power law on more than 11 decades on particle energy, so that the dependence of cosmic ray intensity on particle energy is close to E 2-7 at energy more than about 10 GeV. Closer examination reveals some structure in the galactic cosmic ray spectrum that includes the knee at 4 x 1015 eV, the second knee at about 1018 eV, and the ankle at 1019 eV. The steady-state spectrum is shaped by two principle processes - the acceleration at the sources and the subsequent propagation in the Galaxy. [Pg.131]

At present, the main problem of the data interpretation centers around the second knee in the cosmic ray spectrum. The natural assumption that all individual ions have only one knee at 4 x 1015 Z eV and that the knee in the... [Pg.138]

It is worth noting that the knee observed in the cosmic ray spectrum at 4 x 1015 eV may arise not in the sources but in the process of cosmic ray propagation in the Galaxy, e.g. as a result of interplay between ordinary and Hall diffusion in galactic magnetic fields [54], [Roulet 2004], Of course, this explanation requires the existence of a power-law source spectrum which extends without essential breaks up to about 1018 eV or even further. [Pg.140]

Data on the high energy cosmic ray spectrum are uncertain largely because of limited event statistics due to the very low flux which might best be measured in particles per square kilometer per century. The highest energy event recorded to 1995 had an energy of 3 x 10 " eV (D,J, Bird et al, 1993),... [Pg.1963]

Cosmic ray knee At about 5 x 10 eV, or 5 PeV, there is a small bend downward in the cosmic ray spectrum by about 0.4 in spectral index, from 2.7 to 3.1. [Pg.30]

Cosmic ray spectrum The number of particles at a certain energy E within a certain small energy interval dE is called the spectrum. Flux is usually expresssed as the number of particles coming in per area, per second,... [Pg.30]

Cosmic ray knee. At about 5 x lO eV, or 5 PeV, there is a small bend downward in the cosmic ray spectrum, by about 0.4 in spectral index, from 2.7 to 3.1. This feature is called the knee. There is some evidence that it occurs at a constant energy-to-charge ratio for different nuclei. There is also considerable evidence that toward and at the knee the chemical composition slowly increases in favor of heavier nuclei such as iron. A similar somewhat weaker feature is suggested by new AGASA and HIRES data near 3 x 10 eV, where again the spectrum turns down a bit more. [Pg.33]


See other pages where Cosmic ray spectrum is mentioned: [Pg.319]    [Pg.324]    [Pg.444]    [Pg.4]    [Pg.19]    [Pg.29]    [Pg.138]    [Pg.139]    [Pg.142]    [Pg.221]    [Pg.101]    [Pg.745]    [Pg.105]    [Pg.313]    [Pg.9]    [Pg.33]    [Pg.76]    [Pg.207]   
See also in sourсe #XX -- [ Pg.19 , Pg.221 , Pg.367 ]




SEARCH



Cosmic

Cosmic rays

Cosmics

Ray Spectra

© 2024 chempedia.info