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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 Atmospheric Nucleus p- po g g e+ eg g e- Creating: Electromagnetic p+ “Secondary” Cosmic Rays... (about 50 produced after first collision) po g p- p+ nm m+ muon neutrino Hadronic Shower Shower (muons and neutrinos (electrons and g-rays) reach earth’s surface) Plus : Neutrons Additional Particles from the Thunderstorm Clouds Aragast Solar Neutron Telescope Construction of the SEVAN basic unit 100 – traversal of the low energy charged particle (~<200MeV); 010 – traversal of the neutral particle; 111 & 101 – traversal of the high energy muon (~>250MeV); Starting of SEVANs in Bulgaria and Croatia Selection of Secondary Cosmic Rays at Aragats research station 3200 m a.s.l. Gam m a Elect ron Muon Neut ron Regist ered part icles Purit y by special com binat ion Low energy charged part icles [ 100] 11.605 43.300 37.380 2.838 Neut ral Part icles [ 010] 50.612 8.837 4.494 35.071 High energy charged part icles [ 101] + [ 111] 0.002 0.106 94.904 0.808 Regist ered part icles Purit y by count rat e of t he det ect ors Upper Det ect or 7.616 28.952 56.080 2.448 Middle Det ect or 11.550 5.223 67.913 11.038 Lower Det ect or 2.696 4.438 85.873 3.267 Prot on 4.804 0.972 4.077 4.814 4.167 3.634 Purity-Efficiency Diagram Relativistic feedback breakdown (RFB) In this mechanism, avalanches of runaway electrons emit bremsstrahlung x rays that may either Compton 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 evidence 21 May 2009, AMMM Blue – electrons > 10 MeV Pink – muons > 5 GeV 33000 32000 31000 30000 29000 3 June 2009, AMMM 28000 27000 26000 25000 16:19 16:36 16:52 17:09 UT 17:26 17:43 Relative accuracy ~0.3%; Enhancements 25% at May 21 and 9% at June 3 Intensity[particles/min m sq] Intensity [particles/min m sq] 34000 34000 33000 32000 18:00 31000 30000 29000 28000 27000 26000 25000 15:36 16:04 16:33 UT 17:02 17:31 ASNT: Histograms of additional particles ASNT: Intensities and coincidences ASNT evidence: RFB electrons and Gammas Energy Spectra of RBF gamma-quanta 21 May 2009 Intensity [particles/sq.m min] 8500 8000 7500 7000 6500 6000 5500 5000 16:19 16:33 16:48 17:02 17:16 Time (UT) 17:31 17:45 18:00 RBF Gammas and Electrons detected by SEVAN RFB Neutrons 21 May, 2009 20 16 14 11 12 10 6 8 Dst (nT) Relative increase of neutrons and neutral particles 18 16 6 1 4 2 -4 0 16:30 17:00 17:30 UT By ANM By Sevan (010) Dst by Kyoto MM Additional 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 May 21, 2009; 17:03-17:20 Average count per minute Total Count of additional particles Detector Surface Mean Intensity AMMM ASNT (60 cm) Time of maximal flux UT Maximal minute Intensity #/m2 Comments m2 #/m2/min 703,932 ± 2295 1,408,347 26 3,009 17:16 6,448 Threshold 102,035 ± 399 57,096 3 1,057 17:15 1,769 Efficiency ~ 5-10%; ~10 MeV One of 4 detectors was not in operation ASNT (5 cm) 78,099 ± 304 54,993 4 764 17:15 1,769 Threshold ASNT (11) 8643 ±92 2470 3 46 17:15 115 Threshold 25-30 MeV SEVAN Aragats 100 12,869 ±115 13,206 1 734 17:15 1800 Threshold ~15 MeV SEVAN Aragats 010 1566 ±44 1,507 0.25 335 17:16 1188 Efficiency 1-2% ANM 33,308±212 2542 18 25 17:16 48 Efficiency 1-3%; Duration 17:09 – 17:18 ~15 MeV Electron-photon cascade development and lightings % of mean count rate 120 17:20 115 110 17:11 17:07 105 100 95 90 17:00 17:05 17:10 17:15 17:20 17:25 Time 010 (gamma-quantum) 100 (electrons) 17:30 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!!! 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 EAS are composed of three basic components: the nuclear active component, made up of very highenergy 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 rays from 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 affected by 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 and positrons in the other, depending upon the electric field direction. 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 the high-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 enters through 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 RBF amplifies Radiosignals from EAS Only a fraction of the events recorded during fair weather conditions has a detected 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 Conclusion • First 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 Aragats 0.01 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.