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Spectrum of Gamma Rays, Produced by the Runaway Electrons G.G. Karapetyan Alikhanian National Laboratory, Armenia. In electric field of thunderstorm, the electrons can be accelerated to great energies and produce radiation [1].
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Spectrum of Gamma Rays, Produced by the Runaway ElectronsG.G. Karapetyan Alikhanian National Laboratory, Armenia
In electric field of thunderstorm, the electrons can be accelerated to great energies and produce radiation [1] [1] C.T.R. Wilson “The acceleration of betta-particles in strong electric fields such as those of thunder-clouds”, Proc.Cambridge Philos. Soc., v.22, 534-538, 1924
Terrestrial gamma-ray flashes (TGF) were discovered by satellite observations [2]-about 50 TGFs occur per day-they are ~0.1…10ms pulses, emitted from the top of thunder clouds-bremsstrahlung of accelerated electrons [2] G.J. Fishman et al “Discovery of intense gamma ray flashes of atmospheric origin” Science, v.264, 1313-1316, 1994
Theory of relativistic runaway electron avalanche (RREA) [3] [3] A.V. Gurevich et al, “Runaway electron mechanism of air breakdown and preconditioning during a thunderstorm”, Phys. Lett. A, 165, 463– 468, 1992.
Spectrums of RE were derived by MC simulationsS(E)~exp(-E/7MeV) p=1atm [5] L.P. Babich et al, Geomag. Aeronomija,v 44, N5, pp.697-703,2004
Cross section for bremsstrahlung of ultra relativistic electron [4]E>>mc2, E1>> mc2 and ћw>> mc2 mc2=0.51MeV [4] V.B. Berestecki et al “Relativistic Quantum theory of Field” 1968, p. 424
Ground based measurements of long duration gamma pulses (LDGP) [5] Aragats measurements [5] M. Brunetti et al “Gamma-ray bursts of atmospheric origin in the MeV energy range”, Geoph.Res.Lett., v. 27(11) pp. 1599-1602, 2000
Questions, which have to be answered by theoretical modeling • What is the mechanism underlying LDGP? • Why LDGP were detected by ground based and newer by spacecraft detectors? • How broken energy (~7MeV) is derived? Why it weakly depends on electric field? • What is the maximal energy of LDGP quanta?