Autor: |
Golenetskii, S. V., Mazets, E. P., Aptekar, R. L., Guryan, Yu. A., Ilyinskii, V. N. |
Zdroj: |
Astrophysics and Space Science; July 1986, Vol. 124 Issue: 2 p243-278, 36p |
Abstrakt: |
The emission features observed in the energy spectra of cosmic gamma-ray bursts imply the existence of two radiation components of comparable intensity. The softer component is similar to the continua of featureless bursts. The fast decrease in the intensity of this radiation with increasing photon energy is apparently due to the neutron star's magnetosphere being opaque to hard photons because of the formation of electron-positron pairs in single- (?,B) and two-photon (?,?), processes. The hard component originates from the annihilation of electron-positron pairs, its spectrum representing a broad line with an extended power-law wing. Such a shape of the spectrum is apparently due to either thermal broadening in a source with a spatially inhomogeneous and rapidly time-varying plasma temperature, or nonthermal energy distribution of particles in their motion along the magnetic field lines. It is assumed that the sources of these components are spatially separated, the annihilation radiation escaping from the polar regions of a strongly magnetized neutron star in a collimated beam without appreciable attenuation. |
Databáze: |
Supplemental Index |
Externí odkaz: |
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