Spectrum Of Relativistic Electrons Research Articles

The spectra of radiation and relativistic electrons formed by Compton scattering at non-zero particle fluxes

The formation of steady-state spectra of radiation or particles by Compton scattering is discussed for the case when the flux from the source is present. Power-law distributions, or those characterized by a power-law asymptotic behaviour, can appear under these conditions.

Effect of a magnetic field on the spectrum of relativistic electrons in a plasma turbulent reactor

Our study shows the universality of the power-law spectrum with γ=3 in PTR in the presence of a magnetic field. This result is important to astrophysical applications because there is no doubt that magnetic fields are present in many different types of cosmic objects. This universality can be compared with the known statistical analysis of the spectra of various cosmic radio sources (Fig. 5); the most probable value is close to γ=3. The spread in the observed values of γ could be due to the escape of particles, nonuniformity, and so on, and requires further study.

Processes of comptonization and spectra of relativistic electrons in a turbulent plasma reactor

Processes of comptonization and spectra of relativistic electrons in a turbulent plasma reactor

Inverse Compton Radiation and the Magnetic Field in Clusters of Galaxies

view Abstract Citations (61) References (13) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Inverse Compton Radiation and the Magnetic Field in Clusters of Galaxies Harris, D. E. ; Romanishin, W. Abstract Radio observations below 200 MHz are reported for the cluster Abell 401. These data together with Uhuru X-ray measurements and relevant data for other clusters of galaxies are interpreted in terms of an ensemble of relativistic electrons producing radf6 emission by the synchrotron process and X-rays by the inverse Compton process. Formulae are presented which relate the observations to the relativistic electron spectra: magnetic fields of 10- to 10-8 gauss and total energies of 1062 to 1063 ergs are required. We believe that the enticaltest of the inverse Compton;model will come from X-ray observations between 10 and 100 keV and have calculated X-ray intensities predicted for these energies.' Subject headings: galaxies, clusters of - magnetic fields - radio radiation - synchrotron radiation - X-ray sources Publication: The Astrophysical Journal Pub Date: March 1974 DOI: 10.1086/152707 Bibcode: 1974ApJ...188..209H full text sources ADS |

Omnidirectional induced compton scattering by relativistic electrons

Quasars, pulsars and other cosmic sources of intense radiation are known to have large brightness temperature (kTb≫mc2) and relativistic electron density values. In this case the induced Compton scattering by relativistic electrons should be considered. The probability of scattering with decreasing radiation frequency is derived for isotropic radiation scattering. When induced scattering takes place, the relativistic electron obtains its energy by transforming high-frequency quanta into the low-frequency ones. In the most intensive sources electrons would receive energiesE≃mc2××(kTb/mc2)1/7 due to the heating rate proportional toE−5 with the cooling rate proportional toE2. Considerable distortion of the quasar spectrum is possible for reasonably large values of relativistic electron density (N≳106cm−3) notwithstanding that the heating is negligible. In pulsars relativistic electron heating and spectrum distortion appear to depend more on the induced Compton scattering.

On the Energy Spectrum of Relativistic Electrons in the Crab Nebula

A model of pulsars by Sturreck predicts that pulsars may be sources of large numbers of relativsitic electrons and positrons created by photon decay of high-energy r-rays in the strong magnetic fields of the pulsars. This model is investigated in detail to obtain the energy spectrum of the particles. An energy spectral index of 3/2 is found for the mildly relativistic electrons, which is in extent agreement with the spectral index of electrons that must be injected into the Crab Nebula to give the observed radio spectrum via synchrotron radiation. Further, their number is sufficient to explain the overall energeties of the Crab Nebula. The energies of the secondary particles are sufficient to explainthe optical emission, but not the X-ray flux, via a synchrotron preceas. However, their number aad spectrum strongly suggest that they may be the seed particles that arm accelerated to higher energies before radiation X-rays. (auth)

On a possible mechanism responsible for the differential energy spectrum of relativistic electrons and non-linear low-frequency spectra of cosmic radio sources

The paper suggests an explanation of the deviations from the power law which are observed in frequency spectra of discrete radio sources at decametric wavelengths. It has been shown that a possible mechanism of the deviations is a combined effect of the stimulated and spontaneous scattering of relativistic electrons in the turbulent plasma of a source, as well as ionization energy losses thereof. The distribution function of the relativistic electrons, empirically established in an earlier paper (Braudeet al., 1971) has been derived from the kinetic equation. For a number of discrete sources the turbulence energy density and the plasma concentration are deduced with the aid of experimental data on low-frequency radio spectra.

The interpretation of non-linear radio spectra of discrete radio sources by a general mechanism

The analysis of discrete radio sources spectra in the range 10–5000 MHz reveals that deviations from a power law in the low-frequency region may be due to distortion of differential energy spectra of relativistic electrons at low energies. An empirical expression for an energy-spectrum law was found to be in a good agreement with most of the radio spectra measured. The main physical parameters of 92 sources are evaluated. It is concluded that a low-energy electron excess exists with respect to the lawE−γ in most of the discrete sources which radiate non-linear low-frequency spectra.

On the spectrum of relativistic electrons accelerated in cosmic-ray sources

The data on the spectrum of the cosmic-ray electron component near the earth, on the radio-spectra of radio-galaxies, quasars and the Crab Nebula, as well as the data pertaining to the X-ray spectrum of the cosmic background, all agree that the sources of cosmic-ray electrons (such as supernovae and galactic nuclei) inject particles characterized by a power spectrumN(E)=KE−γ0, with γ0≃1.5–2.5. A mechanism is known in which the source emits a proton-nuclear component of cosmic rays with a spectrumNn(E)=KnE−γn, γn = δ + 2, δ=wcr/(w−wcr), wherewcr is the cosmic-ray energy density in the source, andw=wcr+wn+wturb, the total energy density. We obtain γ=2.5 in agreement with observations on the natural assumption that δ=0.5. Within the framework of the same model with some additional assumptions, the electrons in the source, as well as those ejected by the source, are shown to have a power-spectrum characterized with γ0 ≤ γn = δ + 2. Thus the model discussed gives an adequate spectrum for both the proton-nuclear and the electron components of cosmic rays.

The effect of compression and expansion of plasma on the generation of synchrotron radiation

We consider the variation of the synchrotron-flux density of relativistic electrons with the power law spectrum when the region of generation of this emission initially experiences a homogeneous compression and then an expansion. Ionization losses have been taken into account. The velocities of compression and expansion have been taken as constant. It is shown that in the cases of compression or expansion the flux density at a given frequency changes asS(t) ~ S0Kγ(t)where S0 = flux density before the compression, γ = index of the power law spectrum, K(t) = (H(t))/(H0 (t = 0)), and H is the magnetic-field strength. In the case of compression K(t) > 1·0 and in the case of expansion K(t)< 1·0.The results obtained are applied to an explanation of the increasing and decreasing parts of impulsive bursts of the centimeter range. Such a description of the impulsive bursts has allowed us to estimate both the parameters of the radiating region and the parameters of the differential energetic spectrum of relativistic electrons.

Studies in Radio Structure: II. The Relaxation of Relativistic Electron Spectra in Self-Absorbed Radio Sources

Studies in Radio Structure: II. The Relaxation of Relativistic Electron Spectra in Self-Absorbed Radio Sources