This radiation is a flux of the nuclei of chemical elements, protons for the most part, accelerated to high energies as a result of supernova explosions.*
Such a hypothesis was advanced back in the 1950s. It got a substantial confirmation when Acad. Vitaly Ginzburg (Nobel Prize, 2003) found that nonthermal radio-frequency radiation emanating from supernova remnants (SNR) is generated in magnetic fields by high-energy electrons with a spectrum close to that of cosmic rays.
What remained was experimental proof that a nuclear reaction of cosmic rays likewise occurs in SNR, that is understanding the mechanism of acceleration. According to Acad. Germogen Krymsky (Institute of Cosmophysical Studies and Aeronomy, Siberian Branch of the Russian Academy of Sciences), a good deal of work has been done both in theory and in experimental studies to solve these two problems. As shown by research findings of the past two- three years, both have been clarified.
To detect the nuclear component of cosmic rays in SNR our physicists and astronomers joined hands in a cooperative effort and built super telescopes (designed by Acad. Pavel Cherenkov) capable of registering gamma radiation in the region of several TeV.** Such emissions were thought to be produced with the decay of neutral pions generated by the nuclear component.
Simultaneously a team of researchers under Dr. Yevgeny Berezhko (Institute of Cosmophysical Studies and Aeronomy, Siberian Branch of the Russian Academy of Sciences) came up with a theory postulating generation of cosmic rays by shock waves in SNR. Since in the process of acceleration a significant part of energy is imparted to cosmic rays, it was important to consider their reverse impact-that is the formation of an extended forefront and generation of magnetic turbulence. For this purpose one had to use the nonlinear theory and synthesize an effective computational algorithm. A new method for solving computational problems devised by our scientists is millionfold superior to those used in elsewhere.
Acad. Krymsky went on to say that the nonlinear theory determines not only the spectrum but also the absolute value of energy. These characteristics allowed to calculate the parameters of radio-frequency radiation and X-ray and gamma emissions for each SNR and collate the data thus obtained with the available evidence.
This theory provides a correct description of radiation parameters, and its predicted values agreed with the data on gamma radiation in the TeV region detected in the SNR zone. Radial distribution of X-radiation generated by electrons in the SNR magnetic field proved to be an acid test of the theory. This radiation had to have a "shelled" structure due to energy losses in electrons. The stronger the magnetic field, the thinner the X-ray shell. A comparison of theoretical with observational data made it possible, for the first time ever, to measure the SNR magnetic field and find it to be intensified twofold compared with the typical values in the ambient space.
The high magnetic value in SNR reduces by 3 to 4 orders the number of high-energy electrons assessed
* See: V Orayevsky, V. Kuznetsov, "The Sun, the Earth, and the Stars...", Science in Russia, No. 5, 2002. -Ed.
** See: Yu. Markov, "Space Telescopes", Science in Russia, No. 1,2002. -Ed.
стр. 12
Satellite CORONAS-F in orbit. It is designated for comprehensive studies of the sun (solar flares, plasma elections, active regions) in a wide band of wavelength-from optics to gamma, and also of Solar cosmic rays.
Satellite CORONAS docked with the CYCLONE rocket before launch on the Plesetsk spacedrome.
according to radio-frequency radiation. Accordingly, electrons cease to operate as a proposed alternative source of gamma radiation in the TeV range, which might appear due to the reverse Compton effect.*
So, considering the magnetic field intensification effect, the discovered high-energy gamma radiation clearly attests to the presence of the nuclear component of cosmic rays in supernova remnants, while its parameters are consistent with theoretical values.
Germogen Krymsky, "The Problem of the Origin of Cosmic Rays Solved", Nauka v Sibiri (Science in Siberia), No. II, 2006
Prepared by Yaroslav SIBIRTSEV
* Compton effect discovered by the American physicist Arthur H. Compton (1892 - 1962, Noble Prize, 1927)-shape-elastic scattering of electromagnetic short wavelength radiation (X-ray and gamma-ray emission) on free electrons. This effect confirmed the validity of quantum theory ideas about electromagnetic radiation as a flux of photons and can be viewed as an elastic collision of two "particles"-photon and electron, whereby the photon loses part of its energy (and momentum) to the electron and thus increases the wave-length. Ed.
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