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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

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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

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Page 1: A.Chilingarian Yerevan Physics Institute, Armenia

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

Page 2: A.Chilingarian Yerevan Physics Institute, Armenia

“Primary” Cosmic Ray (Ion, for example a proton)

Atmospheric Nucleus

o -

e e

e

Electromagnetic Shower

o

-

(electrons and -rays)

muon

neutrino

Hadronic Shower

(muons and neutrinos reach earth’s surface)

“Secondary” Cosmic Rays...(about 50 produced after first collision)

Cosmic Ray “Showers”

Space

Earth’s atmosphere

Plus :Neutrons

Creating:Creating:

Page 3: A.Chilingarian Yerevan Physics Institute, Armenia

Additional Particles from the Thunderstorm Clouds

Page 4: A.Chilingarian Yerevan Physics Institute, Armenia

Aragast Solar Neutron Telescope

Page 5: A.Chilingarian Yerevan Physics Institute, Armenia

100 – traversal of the low energy charged particle (~<200MeV);

010 – traversal of the neutral particle;

111 & 101 – traversal of the high energy muon (~>250MeV);

Construction of the SEVAN basic unit

Page 6: A.Chilingarian Yerevan Physics Institute, Armenia

Starting of SEVANs in Bulgaria and Croatia

Page 7: A.Chilingarian Yerevan Physics Institute, Armenia

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

Gamma Electron Muon Neutron Proton Registered particles Purity by special combination

Low energy charged particles [100] 11.605 43.300 37.380 2.838 4.804 Neutral Particles [010] 50.612 8.837 4.494 35.071 0.972

High energy charged particles [101]+[111] 0.002 0.106 94.904 0.808 4.077 Registered particles Purity by count rate of the detectors

Upper Detector 7.616 28.952 56.080 2.448 4.814 Middle Detector 11.550 5.223 67.913 11.038 4.167 Lower Detector 2.696 4.438 85.873 3.267 3.634

Page 8: A.Chilingarian Yerevan Physics Institute, Armenia

Purity-Efficiency Diagram

Page 9: A.Chilingarian Yerevan Physics Institute, Armenia

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.

Page 10: A.Chilingarian Yerevan Physics Institute, Armenia

AMMM evidence

21 May 2009, AMMM

25000

26000

27000

28000

29000

30000

31000

32000

33000

34000

16:19 16:36 16:52 17:09 17:26 17:43 18:00UT

Inte

nsity [p

art

icle

s/m

in m

sq

]

3 June 2009, AMMM

250002600027000

28000290003000031000

320003300034000

15:36 16:04 16:33 17:02 17:31

UT

Inte

nsi

ty[p

artic

les/

min

m s

q]

Blue – electrons > 10 MeVPink – muons > 5 GeV

Relative accuracy ~0.3%;Enhancements 25% at May 21 and 9% at June 3

Page 11: A.Chilingarian Yerevan Physics Institute, Armenia

ASNT: Histograms of additional particles

Page 12: A.Chilingarian Yerevan Physics Institute, Armenia

ASNT: Intensities and coincidences

Page 13: A.Chilingarian Yerevan Physics Institute, Armenia

ASNT evidence: RFB electrons and Gammas

Page 14: A.Chilingarian Yerevan Physics Institute, Armenia

Energy Spectra of RBF gamma-quanta

21 May 2009

5000

5500

6000

6500

7000

7500

8000

8500

16:19 16:33 16:48 17:02 17:16 17:31 17:45 18:00

Time (UT)

Inte

ns

ity

[p

art

icle

s/s

q.m

m

in]

Page 15: A.Chilingarian Yerevan Physics Institute, Armenia

RBF Gammas and Electrons detected by SEVAN

Page 16: A.Chilingarian Yerevan Physics Institute, Armenia

RFB Neutrons21 May, 2009

-4

1

6

11

16

16:30 17:00 17:30

UT

Rel

ativ

e in

crea

se o

f ne

utro

ns a

nd n

eutr

al

part

icle

s

0

2

4

6

8

10

12

14

16

18

20

Dst

(n

T)

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

Page 17: A.Chilingarian Yerevan Physics Institute, Armenia

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

m2

Mean Intensity

#/m2/min

Time of maximal flux UT

Maximal minute Intensity #/m2

Comments

AMMM 703,932 ± 2295 1,408,347 26 3,009 17:16 6,448 Threshold ~10 MeV

ASNT (60 cm)

102,035 ± 399 57,096 3 1,057 17:15 1,769 Efficiency ~ 5-10%;

One of 4 detectors was not in operation

ASNT (5 cm)

78,099 ± 304 54,993 4 764 17:15 1,769 Threshold ~15 MeV

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

Page 18: A.Chilingarian Yerevan Physics Institute, Armenia

Electron-photon cascade development and lightings

Page 19: A.Chilingarian Yerevan Physics Institute, Armenia

Electrical field measurements and particle enhancements

Page 20: A.Chilingarian Yerevan Physics Institute, Armenia

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

Page 21: A.Chilingarian Yerevan Physics Institute, Armenia

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

Page 22: A.Chilingarian Yerevan Physics Institute, Armenia

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.

Page 23: A.Chilingarian Yerevan Physics Institute, Armenia

RBF amplifies Radio-signals from EAS

Only 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

Page 24: A.Chilingarian Yerevan Physics Institute, Armenia

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;

Page 25: A.Chilingarian Yerevan Physics Institute, Armenia

Radio-band-width monitoring detection at Aragats

Page 26: A.Chilingarian Yerevan Physics Institute, Armenia

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.