Runaway Breakdown and its Implications. Gennady Milikh University of Maryland, College Park, MD in collaboration with Alex Gurevich, Robert Roussel-Dupre, Surja Sharma, Parvez Guzdar, Juan Valdivia and Dennis Papadopoulos.
University of Maryland, College Park, MD
in collaboration with Alex Gurevich, Robert Roussel-Dupre, Surja Sharma, Parvez Guzdar, Juan Valdivia and Dennis Papadopoulos
Workshop on the multiscale nature of spark precursors & HAL – Leiden, May 2005
- Intracloud X-ray pulses & charge transfer
- Gamma-Ray Bursts
- Terrestrial Gamma-Ray Flashes
- Narrow Bipolar Pulses
At Dreicer field the bulk of fully ionized plasma becomes runaway [Dreicer, 1960].
However, even at fast electrons run away.
In the weakly ionized plasma the interactions between high energy electrons and particles obey the Coulomb law. If E-field exceeds the critical value the whole bulk of electrons accelerated [Gurevich, 1961]
For relativistic electrons [Bethe & Ashkin, 1953] the friction force reaches its minimum at
Dynamical friction force as a function of the Lorentz factor
Although the bulk of secondary electrons caused by the impact ionization of relativistic electrons has low energy, some fast particles with
are also produced. This leads to runaway breakdown.
4 km [Eack et al., 1996]
(the bottom plate).
The electric field (the top Plate), the soft component (electrons, 10-30MeV) of cosmic rays (second from the top) observed during the thunderstorm on 09/07/00. The arrows show lightning strokes. The largest pre-lightning enhancement lasts about 0.5 min (after Alexeenko et al, 2002).
The map shows the global thunderstorm activity, while the crosses reveal where the TGFs were observed.
[Smith et al., 2005]
Examples of TGFs and their energy spectrum.
Positive NBP (left) and negative NBP (right) observed by Los Alamos Sferic Array [Smith et al., 2002] (and the FORTE satellite). Time is given in mcs.
- Cloud-to-ground discharge
- Intracloud discharge
Model Assumptions [Gurevich & Milikh, 1999]:
Computed for z=4 km, unidirectional differential intensity of cosmic ray secondary from Daniel and Stephens , and E/Eco=2.
Here red points show the real measurements, blue – model at 70 m from the sources, green – model at 420 m from the source.
It is driven by a static electric field due to:
[Gurevich et al, 2004; Milikh et al., 2005].
Runaway Electron Beam
+ + + + +
_ _ _ _ _ _ _
Gamma-ray bursts in the presence of thunderclouds [Milikh et al., 2005]
+ + + + + + +
shows that an instability can develop in the system driven by the relative drift between the hot and cold electrons.
Fig. 3. The behavior of the peak growth rate as a function of altitude. Maximum is at about 30 km.
Fig. 4. The dependence of the peak growth rate upon the number density of the hot electrons.
Runaway beam starts at a certain height and moves up if
When it reaches magnetization height the instability develops.
is needed in order to provide:
and i.e. the burst-time of gamma-ray flashes.
The runaway breakdown starts with a primary particle
which generates MeV particles [Gurevich et al., 1999].
Then runaway develops and produces relativistic
spreading in a volume , thus their density .
versus the distance.
Thus is required, and the length of the r-away
discharge is 2.5 km.
Such conditions for runaway breakdown are similar to those leading to generation of strong bipolar pulses [Smith et al., 2002; Jacobson, 2003]. The latter are a manifestation of runaway breakdown occurs at 18-20 km simulated by a cosmic particle of [Gurevich et al., 2004].
Red trace – no pumping wave,
Green trace – pumping exists
in the drama of lightning
Gurevich & Zybin, 2005
Alekseenko et al., Phys. Lett. A, 301, 299, 2002.
Bell, T. F., V. P. Pasko, and U. S. Inan, Geophys. Res. Lett., 22, 2127, 1995.
Bethe, H. A., and J. Ashkin, Passage of radiations through matter, in Experimental Nuclear Physics (ed. E. Segre) Wiley, New York 1953, pp. 166-357.
Daniel, R. R., and S. A. Stephens, Rev. Geophys. Space Sci., 12, 233-258, 1974.
Dreicer, H., Phys. Rev., 117, 329-342, 1960.
Dwyer, J.R., et al., Geophys. Res. Lett., 31, L05119, 2004.
Eack, K. B., et al., Geophys. Res. Lett., 23, 2915, 1996.
Feldman, W. C., E. M. D. Symbalisty, and R. A. Roussel-Dupre, J. Geophys Res, 101A, 5195, 1996a.
Feldman, W. C., E. M. D. Symbalisty, and R. A. Roussel-Dupre, J. Geophys Res, 101A, 5211, 1996b.
Fishman, G. J., P. N. Bhat, R. Mallozzi, et al., Science, 264, 1313, 1994.
Gurevich, A. V., Sov. Phys. JETP, 12, 904-912, 1961
Gurevich, A. V., G. M. Milikh, and R. Roussel-Dupre, Phys. Lett. A, 165, 463, 1992.
Gurevich, A.V., and G.M. Milikh, Phys. Lett. A., 262, 457, 1999.
Gurevich A.V. et al., Phys. Lett. A, 260, 269, 1999.
Gurevich, A. V., Y. V. Medvedev, and K. P. Zybin, Phys Lett. A, 329, 348, 2004.
Jacobson, A.R., J. Geophys. Res., 108D, doi:10.1029/2003JD003936.
Kaw, P. K., G. M. Milikh, A. S. Sharma, P. N. Guzdar and K. Papadopoulos, Phys. Plasmas, 8, 4954, 2001.
Lehtinen, N. G., N. Walt, T. F. Bell, U. S. Inan, and V. P. Pasko, Geophys. Res. Letts., 23, 2645, 1996.
Lehtinen, N. G., T. F. Bell, and U. S. Inan, J. Geophys. Res., 104A, 24699, 1999.
Lehtinen, N. G., U. S. Inan, T. F. Bell, J. Geophys. Res., 106A, 28841, 2001.
Marshall, T. C., M. Stolzenburg, and W. D. Rust, J. Geophys. Res., 101A,6979-6996, 1996.
McCarthy, M.D. nd G.K. Parks, Geophys. Res. Lett., 12, 393, 1985.
Milikh, G.M, P.N. Guzdar, and A.S. Sharma, J. Geophys. Res., 110, doi: 10.1029/2004JA0106681, 2005.
Moore, C.B. et al., Geophys. Res. Lett., 28, 2141, 2001.
Nemiroff, R. J., J. T. Bonnel, and J. P. Norris, J. Geophys. Res., 102, 9659, 1997.
Roussel-Dupre, R, A. V., Gurevich, T. Tunnel, and G. M. Milikh, Phys. Rev. E, 49(3), 2257, 1994.
Roussel-Dupre, R., and A. V., Gurevich, J. Geophys. Res., 101, 2297, 1996.
Smith, D. A., et al., J. Geophys. Res., 107D, doi: 10.1029/2001JD000502, 2002.
Smith, D. M. et al., Science, 307, 1085, 2005.
Taranenko, Y. N., and R. Roussel-Dupre, Geophys. Res. Letts., 23, 571, 1996.
Yukhimuk, V., R. A. Roussel-Dupre, E. M. D. Symbalisty, Geoph. Res. Lett., 26, 679, 1999.