Title :
Theoretical and experimental researches of the ability to create the long conductive cannel in the atmosphere
Author :
Stupitsky, E.L. ; Morozov, D.V.
Author_Institution :
Moscow State Ind. Univ., Sergiev Posad, Russia
Abstract :
Summary form only given. This paper discovered the results of series of theoretical and experimental researches of the ability to create the conductive channel with length of 50 - 100 m in normal atmosphere by directional flux of radiation. This channel is essential condition for creation nonlethal means for influence on bio object and electro-technical devise by pulse current. Currently existing electric shocks own range of influence ~ 1 m. The amplitude value of current Im = 25 - 50 mA and pulse length ζ= 3 - 5 ms represent practical interest for influence on bio objects. We proved that it requires support for in atmosphere the level of electron density ~ 108 - 1011 cm-3. Calculations have shown that energy density flux (W/cm2), comparable with the threshold value for Nd and Rb, are required for the effect of the photoionization of air molecules by laser radiation (Nd, Rb). We carried out detailed studies of the capability of the ultraviolet discharge emitters for obtain the necessary by the mechanism of stepwise ionization via the intermediate electron excited states of molecules N2 and O2. The kinetic scheme includes five lower electronic states of O2 and four electronic states of N2. We proved, that with accepted mechanism of fotoionisation and without geometric divergence of the beam the concentration of electrons along the channel decay very slow: n~ 1/ √x. This suggests that the necessary ~ 108 - 1011 cm-3 can be achieved within 50 - 100 m with quite achievable values energy flux density in cannel. The length of the pulse should be ~ 30 ms, so as to further radiation is absorbed by ozone. The pulse ultraviolet arc discharge used in experimental investigations with brightness temperature 23000 - 25000 K . The experimental investigations all vindicated dependence ne ~ 1/ √x. However, the value was much lower the calculated valu- (~106 cm-3). Detailed analysis of the optical system showed, that these values are obtained if due to reflection and other losses in the beam are the fraction of energy ~ 3.10-3. Thus, the theoretical and experimental researches proved the principle possibility to create the channel by the pulsed discharge source. The general conditions to create the necessary density of the ultraviolet radiation in the channel is the developing a mirror with high reflectivity in the ultraviolet spectrum (~ 200 nm).
Keywords :
arcs (electric); magnetic mirrors; neodymium; photoionisation; plasma density; plasma light propagation; plasma shock waves; reflectivity; rubidium; ultraviolet spectra; N2 molecules; Nd; O2 molecules; Rb; air molecules; bio object; current 25 mA to 50 mA; electron concentration; electron density level; electronic states; electrotechnical devise; energy density flux; energy flux density; existing electric shocks; geometric divergence; intermediate electron excited states; laser radiation; long conductive cannel; mirror; photoionisation mechanism; photoionization effect; pulse current; pulse ultraviolet arc discharge; pulsed discharge source; radiation directional flux; reflection losses; reflectivity; size 50 m to 100 m; stepwise ionization; temperature 23000 K to 25000 K; time 3 ms to 5 ms; ultraviolet discharge emitters; ultraviolet radiation density; ultraviolet spectrum; Atmosphere; Discharges (electric); Educational institutions; Electric shock; Ionization; Laser beams; Lasers;
Conference_Titel :
Plasma Science (ICOPS), 2012 Abstracts IEEE International Conference on
Conference_Location :
Edinburgh
Print_ISBN :
978-1-4577-2127-4
Electronic_ISBN :
0730-9244
DOI :
10.1109/PLASMA.2012.6384017