a.chilingarian yerevan physics institute, armenia

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Detection of 10-40 MeV electrons, neutrons and gammas from the Relativistic Feedback Breakdown Process by particle detectors at Aragats. A.Chilingarian Yerevan Physics Institute, Armenia. Cosmic Ray “Showers”. Space. “Primary” Cosmic Ray (Ion, for example a proton). Earth’s atmosphere. - PowerPoint PPT Presentation


  • Detection of 10-40 MeV electrons, neutrons and gammas from the Relativistic Feedback Breakdown Process by particle detectors at AragatsA.Chilingarian Yerevan Physics Institute, Armenia

  • Primary Cosmic Ray (Ion, for example a proton)Atmospheric Nucleuspop-p+gge+e-ge-Electromagnetic Showerpop-p+(electrons and g-rays)m+muonnmneutrinoHadronic Shower (muons and neutrinos reach earths surface)Secondary Cosmic Rays...(about 50 produced after first collision)Cosmic Ray ShowersSpaceEarths atmospherePlus : Neutrons


  • Additional Particles from the Thunderstorm Clouds

  • Aragast Solar Neutron Telescope

  • 100 traversal of the low energy charged particle (~250MeV);

  • Starting of SEVANs in Bulgaria and Croatia

  • Selection of Secondary Cosmic Raysat Aragats research station 3200 m a.s.l.

  • Purity-Efficiency Diagram

  • Relativistic feedback breakdown (RFB)

    In this mechanism, avalanches of runaway electrons emit bremsstrahlung x rays that may eitherCompton backscatter or pair produce in the gas medium. If the backscattered photons propagate to the start of the avalanche region and produce another runaway electron, either via Compton scattering or photoelectric absorption, then a secondary avalanche is created. Alternatively, the positrons created by pair production can sometimes turn around in the ambient electric field and run away in the opposite direction of the electrons. The positrons quickly become relativistic, allowing them to travel for many hundreds of meters before annihilating. If these positrons propagate to the start of the avalanche region they can produce additional runaway electrons via hard elastic scattering with atomic electrons in the gas i.e., Bhahba scattering, thereby producing secondary avalanches. These secondary avalanches can in turn emit more x rays that Compton scatter or pair produce, resulting in more feedback and more avalanches. This positive feedback effect allows the runaway discharge to become self- sustaining, no longer requiring an external source of energetic seed electrons. As a result of this positive feedback, the number of runaway electron avalanches increases exponentially on a time scale measured in microseconds.

  • AMMM evidenceBlue electrons > 10 MeVPink muons > 5 GeVRelative accuracy ~0.3%;Enhancements 25% at May 21 and 9% at June 3

  • ASNT: Histograms of additional particles

  • ASNT: Intensities and coincidences

  • ASNT evidence: RFB electrons and Gammas

  • Energy Spectra of RBF gamma-quanta

  • RBF Gammas and Electrons detected by SEVAN

  • RFB NeutronsAdditional neutrons, born in the air are initiated by the hard gamma-quanta in photo-nuclear reactions with air atoms. Existence of neutrons, along with electrons and gammas is another proof of the RFB model

  • Outline of the thunderstorm correlated enhancements at 21 May 2009

  • Electron-photon cascade development and lightings

  • Electrical field measurements and particle enhancements

  • Thunderstorm on August 6, 2003, averaging over 15 s,one of the longest and most profound muon effect Electric field strength

    Soft component

    Muons >1 GeV

    Hard component (muons > 90 MeV)

    Stopping muons (20-80 MeV)Baksan measurements

  • Additional electrons coming vertically!!!EAS are composed of three basic components: the nuclear active component, made up of very high-energy particles close to the shower axis: the muon component, which forms a broad lateral distribution, and the electronic component made up of electrons, positrons, and gamma rays. The electrons and positrons in the air shower are the result of electromagnetic cascades continuously generated by high-energy gamma raysfrom pion decays. At thunderstorm altitudes, the air shower is often near its maximum development. Near shower maximum, most of the particles in the shower are part of the electronic component. As the air shower propagates through a high-field region, due to their high rigidity, the nuclear and muon components are not significantly affectedby the thundercloud electric fields. On the other hand, the electronic component can be substantially altered by the electric field, with electrons deflected in one direction andpositrons in the other, depending upon the electric field direction. J. R. Dwyer,1M. A. Uman,2and H. K. Rassoul, Remote measurements of thundercloud electrostatic fields, JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 114, D09208, doi:10.1029/2008JD011386, 2009

  • Can RBF harm EAS?EAS(blue dots labeled EAS) entering a high electric field region, wherein runaway electron avalanches are produced (black dots). The electric field points upward. The low energy electrons (red dots labeled slow electrons) resulting from ionization by the runaway electrons trail behind the runaway electrons. As the air shower passes through thehigh-field region, the muons and hadronic core are not significantly deflected by the electric force, and so the location that the air shower strikes the ground is unchanged. However, the electric field locally causes large deflections of the electrons (and positrons) in the shower, which make the largest contribution to the runaway electron seed population. For the case of a downward electric field, the air shower still entersthrough the top of the avalanche region, as shown, and propagates to the bottom of the region. However, the runaway electrons and the low-energy electrons all propagate upward in this case. As the runaway avalanches propagate and grow, the increasing electric current produces RF emissionthat can be measured remotely.

  • RBF amplifies Radio-signals from EASOnly a fraction of the events recorded during fair weather conditions has adetected coherent signal. During thunderstorms this fraction is 2.5 times higher.M. Endery, W.D. Apel, J.C. Arteagay et al., Radio Emission of Extensive Air Showers during Thunderstorms, PROCEEDINGS OF THE 31st ICRC, LODZ 2009

  • ConclusionFirst simultaneous detection of high energy gamma-quanta, electrons and neutrons, proving existence of the intensive self-sustaining electron photon cascade process in the atmosphere developing in the Earth direction;Simultaneous measurements of the gamma-rays, electrons and neutrons provide unambiguous confirmation of the photonuclear mechanism for neutron production.First detection of numerous long lasting events of additional particle flux, provided by chain cascade process (positive feedback); RFB can sustain the acceleration process in the atmosphere for up to 30 minutes despite discharge by lightening. First measurement of the energy spectra a of the thunderstorm related gamma-quanta up to 40 MeV;

  • Radio-band-width monitoring detection at Aragats

  • Magnetometry at Aragats0.01 nT accuracy magnetic sensor of flux-gate type, was manufactured using well-proved technology on the base of marble and quartz combination implementing recent findings in the excitation circuit construction. For electric channels, a filter-free technology of input stages was accepted in order to let to pass super-long period signals. In order to avoid the channels saturation in natural electric field, the automatic compensation circuit is provided at the beginning of the measurements in the range 250 mV.

    *When primary rays reach our atmosphere, they run into other atomic nuclei and cause showers of particles. One primary ray can cause 50 secondary rays, a cascading effect that eventually gets down to the ground. The shower of secondaries can spread over a large area. You are constantly being bombarded by these particles.**


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