NEGATIVE POINT

Experimental results

It is known [3] th a t under pure conditions in nitrogen there are tw o different steady sta te m odes o f a point-to-plane discharge. Transition from one sta te to another occurs w ith the appearance o f the current and light pulses sim ilar to those in the case o f a Trichel pulse in air. Our conditions were n ot pure enough and for th a t reason the discharge near the onset p otential existed in a pulsed form.

T h e onset potential o f spontaneous Trichel pulses was 9.2 kV. T h e current pulse achieved its m axim um value o f 5 m A after 5 ns, it was followed by a slow decay and after 1.5 /is a quasistationary value o f 0.2 m A was established ("tail” o f the p u lse).

After the filling o f the discharge chamber w ith pure gas the tail lasted longer than after som e days o f work (F ig. 5). W hen the discharge cham ber w as refilled, the previous pulse duration was achieved. If the laser radiation was directed in to the discharge gap, current pulses were Recorded already at U = 2kV . Charge q = f id t created per pulse as a function o f voltage is presented in Fig. 6 (/o = 3 x 107W /c m 3).

If U < 7 kV , q strongly depended on the laser pulse intensity, the duration and the shape o f the current pulse corresponded to the shape o f the laser pulse.

T ypical schem atic current pulses for [I > 7 kV are presented in F ig. 7. T h e am plitu d e value ima, o f the sharp peak at the beginning o f the current pulse as well as its shape were correlated w ith the laser pulse intensity and its “fine” structure.

For t > 6 0 ns the current pulse tim e dependence did not differ from the sh ap e o f the spontaneous pulse. If / ~ 107W /c m 3, the current pulse had a delay tim e o f id ta 5 ns from the beginning o f the laser pulse. If / — 106YV/cm5 and U = 8.3k V , td = 90ns. T h e laser radiation energy concentration was high enough to cause therm oionic em ission from the point. T hus if we suppose that imax was determ ined by the surface tem perature T (T ~ / ) and the field strength E (U ~ E ) , ln (ima>) m ust be a linear function o f y /U [4]. As we can see in Fig. 8 the a ssu m p tion o f a therm oionic nature o f the electron em ission explains the results recorded in the experim ent quite well. T h e main conclusions are :

94 84

U [kV]

Fi*. 5. Trichel pulse duration as a func- Fig. 6. Charge per pulse {q — f idi) as a tioD of voltage for different conditions. function of voltage for different intensities I.

Fig. 7. Schematic representation of Fig. 8. Logarithm of the imax as a function of

current pulses. y/U for different intensities /.

1. T h e m agnitude of the firet peak o f the current pulse is the function o f E and T .

2. It is possible to create typical TYichel pulses on voltages remarkably lower than th e onset o f a spontaneous one. C onsquently the form ation o f a Trichel pulse is n o t determ ined only by ionization processes in the gas.

3. T h e role o f the laser radiation dim inishes w ith the voltage increase, near the sp on tan eou s pulse onset the dependence o f tmac on the radiation intensity (surface tem perature) is weak.

85

95

V. DISCUSSION

U sually the form ation o f the Trichel pulse is explained by the gas ionization by electrons accelerated in the electric field. T h is m odel was used in M orrow’s theory [5]. T h e existen ce o f a step in the leading part o f the current pulse w as explained by a different influence o f the j p and the л m echanism [6]: at the b eginning o f the pulse j p is active, in the later stages it is replaced by a more effective 7 <

m echanism . A s a result o f our m easurem ents another explanation o f the pulse form ation is available. In [7] it is m entioned that field em ission can play a role in pulse form ation. Field em ission is effective from the m icropoints (or dielectric film s) on the electrode surface [4]. A s a result Joule heating o f these irregularities and their explosion take place. Such a process is an effective source o f electrons.

We suppose th a t the step in the leading part o f the current pulse as well as the

"precursor” before the pulse [8] are due to explosive em ission. Below the onset potential an additional source for electrode heating is needed (in our case - laser radiation).

T h e fact th a t for t > 60 ns the shapes o f the Trichel pulses below and above the onset potential are the sam e indicates that ionization m echanism s in these stages do not differ. R ecently the results o f spectroscopical m easurem ents o f the Trichel pulses have been presented [9,10]: the ionization m echanism by the electron im pact w ith the N 2 ground sta te is active only in the first ten nanoseconds, when the field strength near the point electrode is high enough, later ionization by m eans o f the m etastab le Л-sta te takes place. C onsequently, the duration o f the current tail is connected w ith the concentration o f the Л-sta te m etastables. If the discharge occurs, a sm all am ount o f adm ixtures is released from the electrode surface. A possible m axim um concentration o f im purities is too low to stop the Trichel pulse by quenching the m etastab les. More realistic is an assum ption that these adm ixtures (as it is shown in [11]), which have a lower ionization p otential than N2, m odify the electron distribution function and as a result the rate coefficient o f the Л-sta te ex cita tio n diminishes: with an increasing adm ixture concentration the tail duration o f the current pulse dim inishes.

REFERENCES

[1] K o r g e , H., K u d u, K., L aan , M.: 3rd ISH VE, paper 31.04, 1979.

[2] P o p o v , A. M., et al, Thermophys. High Temperatures USSR, vol. 27 (1989), 173.

[3] K o r g e , H., L aan, M., S u si, J., Acts Comment. Univ. Tartuensis, no. 824 (1988), 25. (in Russian).

4. T h e current pulse tail duration has a strong dependence on im purities.

86 96

[4] K o r o le v , Yu. D., M e s y s t s , G. A., in Field emission and explosive processes in gas discharge. Novosibirsk 1982 (in Russian).

[5] M orrow , R., Phys. Rev. A32 (1985), 1799.

[6l M o rro w R., Phys. Rev. A32 (1985), 3821.

[7] Cern&k, M., Proc. П th ICPIG, Contr.papers (1985), 573.

[8] C e r n a k , М., Кa n e dа, Т., and H o sa k a v a , Т., Jap. Appl. Phys. 28(1989), 1989.

[9] K o rg e, H., L aan , M., S u si, J., 9 th ESCAMP1G, Cont. рарегз (1988), 115.

[10] К o r g e , H., K u u sk , U., L aan, M., S u si, J., Plasma Phys. USSR, 17 (1991), 473.

[11] A p o llo n o v , V., et al. Lett. Techn. Phys. USSR, 13 (1987), 1363.

Received October 18th, 1990

Accepted for Publication January 4th, 1991

ВЛИЯНИЕ ЛАЗЕРНОГО ИЗЛУЧЕНИА НА КОРОННЫЕ ИМПУЛЬСЫ Исследованно влияние УФ лазерного излучения на юронные импульсы. В случае положительного острил получен одноканальныи стример, юторый имел хорошую повторяемость ш в пространстве так и во времени. В случае отрицательного ос­

трия формирование импульса при подпороговых напряжениях объяснимо термоэ- миссиеи, при более высоких напряжениях - взрывной эмиссией.

87 97

STREAMER IHITIATIOH ВТ X-RAY PULSE

M. L a a n , P . P a r i s

F o r t h e e x p e r i m e n t a l i n v e s t i g a t i o n o f a s t r e a m e r f o r m a t i o n t h e e x p e r i m e n t a l e q u ip m e n t m u s t b e w e l l s y n c h r o n i z e d w i t h t h e m oment o f c r e a t i o n o f t r i g g e r i n g e l e c t r o n s . A g o o d s y n ­ c h r o n i z a t i o n ( w h ic h h a s a n a n o s e c o n d j i t t e r ) i n h o m o g e n e o u s f i e l d i s a c h i e v e d b y l i b e r a t i n g t h e f i r s t e l e c t r o n s fr o m t h e c a t h o d e w i t h a s h o r t UV p u l s e . I t i s i m p o s s i b l e t o u s e t h i s m e th o d i n a p o s i t i v e p o i n t - t o - p l a n e d i s c h a r g e g a p , a s t h e f i r s t e l e c t r o n s m u s t b e c r e a t e d i n a s m a l l v o lu m e n e a r t h e p o s i t i v e p o i n t . In [ 1 ] a s t r e a m e r w a s i n i t i a t e d b y X e C l l a s e r ( Л_= 3 0 8 nm) p u l s e . A l t h o u g h a g o o d s y n c h r o n i z a t i o n w a s a c h i e v e d , a d d i t i o n a l d i f f i c u l t i e s a r o s e i n f u r t h e r i n t e r p r e ­ t a t i o n s i n c e t h e l a s e r r a d i a t i o n c a u s e d a r e m a r k a b le v a p o r i ­ z a t i o n o f p o i n t e l e c t r o d e n a t e r i a l .

T he a i n o f t h i s p a p e r i s t o i n v e s t i g a t e t h e s t r e a m e r f o r m a t i o n u s i n g t h e J f -r a y r a d i e t i o n a s ® s o u r o e o f f i r s t e l e c t r o n s .

E x p e r i m e n t a l s e t - u p . A l l t h e e x p e r i m e n t s w e r e c a r r i e d o u t in l a b o r a t o r y a i r a t a t m o s p h e r i c p r e s s u r e . P o s i t i v e D .C . c o ­ r o n a in a p o i n t - t o p l a n e d i s c h a r g e g a p w a s i n v e s t i g a t e d . D i s ­ t a n c e b e t w e e n t h e e l e c t r o d e s w a s 4 cm . T h e p o i n t e l e c t r o d e w a s a h e m i s p h e r i c a l l y c a p p e d P t w i r e 1 on in d i a m e t e r . P la n e e l e c t r o d e w a s a A l d i s c , 15 cn in d i a m e t e r , w i t h 4 mm h o l e in i t s c e n t e r , t h a t m a k e s i t p o s s i b l e t o d i r e c t X - r a y r a d i a t i o n a l o n g t h e d i s c h a r g e g a p a x i s .

T he J f-r a y s o u r c e had a p la s m a c a t h o d e d e s c r i b e d i n [ 2 ] . T he a n o d e w ae p l a c e d a t 4 сю f r o n t h e c a t h o d e . T h e w o r k in g p r e s s u r e w a s 0 . 1 P a . T he J f-r a y t u b e had a l a v s a n w in d o w . 3 0 kV n e g a t i v e p u l s e , h a l f - w i d t h o f w h ic h w a s 1 1 0 n s , w a s s u p p l i e d t o t h e c a t h o d e . J f-r a y p u l s e had в h a l f - w i d t h o f 7 0 n s ( F i g . 2 ) . T h e p o s i t i o n o f J f-r a y p u l s e r e l a t e d t o t h e v o l t a g e p u l s e w a s d e t e r m in e d w i t h a c c u r a c y o f so m e n a n o ­ s e c o n d s . 10 p p s r e p e t i t i o n r a t e o f J f-r a y p u l s e s w a s u s e d . In a b s o r p t i o n m e a s u r e m e n t s f o r J f-r a y q u a n tu m e n e r g y d e t e r m i n a ­ t i o n tw o d i f f e r e n t d e t e c t o r s y s t e m s w e r e u s e d : s c i n t i l l a t o r + p h o t o m u l t i p l i e r and i o n i z a t i o n ch a m b e r + e l e c t r o m e t e r . T he mean q u a n tu m e n e r g y w a s w i t h i n l i m i t s o f 5 - 8 k eV . An ^ f-ray p u l s e o r i g i n a t e d n e a r l y 1 0 7 c h a r g e d p a r t i c l e s p e r cm3 a s

d e t e r n i n e d b y i o n i z a t i o n c h a n b e r .

F i g . l . S k e t c h e s o f b u r s t p u l s e ( A ) an d b u r s t - t o - s t e a n e r t r a n s i t i o n ( B ) . S o l i d l i n e p r e s e n t s t h e t i n e d e p e n d e n c e o f b u r s t p u l s e c u r r e n t , d a s h e d l i n e -t h e s a n e d e p e n d e n c e o f l i g h -t В - t d - t i n e i n t e r ­ v a l b e t w e e n t h e b e g i n n i n g o f t h e J f-r a y p u l s e and t h e s t r e a n e r f o r m a t i o n , r - d u r a t i o n o f t h e b u r s t s t a g e . T r a n s i t i o n o c c u r s a t UQ = 7 . 6 2 kV.

s t r e a m e r . The f i r s t o n e i s q u i t e w e l l r e l a t e d t o t h e Х -т л у p u l s e , t h e n e x t o n o f o l l o w s r a n d o m ly w i t h t h e d e l a y t i n e o f 1 n s an d n o r e . A t v o l t a g e s a b o v e UQ e x i s t b o t h i n i t i a t e d and s p o n t a n e o u s s t r e a m e r s . In F i g . 2 d e l a y t i n e d i s t r i b u t i o n o f t h e f i r s t i n i t i a t e d s t r e a n e r f o r d i f f e r e n t v o l t a g e s an d n e a n Ta d e p e n d e n c e on v o l t a g e a r e p r e s e n t e d ; i n F i g . 3 - £d and 2Q d e p e n d e n c i e s on X - i & y i n t e n s i t y a r e p r e s e n t e d .

D i s c u s s i o n . I t i s a c c e p t e d t h a t i n a h o n o g e n e o u s f i e l d t h e f o r n a t i o n o f a s t r e a m e r i s p o s s i b l e w hen a n u n b e r o f c h a r g e d c a r r i e r s a c h i e v e t h e v a l u e o f 1 0 ® i n an a v a l a n c h e [ 5 ] . T he e x i s t e n c e o f s u c h a m y s t i c num ber d e m a n d s f u r t h e r e x p l a n a t i o n e s p e c i a l l y in t h e c a s e o f in h o m o g e n e o u s p o i n t t o p l a n e g e o -n e t r y w h e r e n e a r t h e o n s e t p o t e n t i a l UQ t h e n a g n i t u d e o f a s i n g l e a v a l a n c h e i s e e v e r a l o r d e r s l e s s t h a n 1 0 8 [ 4 ] .

F o r t h a t r e a s o n a n o t h e r f o r m u l a t i o n s e e m s t o b e m ore p r e ­ f e r a b l e : s t r e a m e r f o r r a t i o n o c c u r s a t t h e n o n e n t w h e n , t h e i o n i z e d g a s a c h i e v e s a p la s m a d e n s i t y i . e . t h e D e b y e l e n g t h rD b e c o m e s l e s s t h a n t h e c h a r a c t e r i s t i c d i m e n s i o n o f i o n i z e d g a s r e g i o n d [ 6 , 7 ] . In o u r c a s e i t m e a n s t h a t b u r s t t o -- s t r e a m o r t r a n s i t i o n i s p o s s i b l e w hen t h e i o n i z e d g a s d e n ­ s i t y in a t h i n l a y e r n e a r t h e p o i n t s u r f a c e a c h i e v e s t h e

0,1

N=1,4 U=7.65W

, 'V * - r a y

' \\\ ъ .

1 0 0 L.ns Us 7,61 kV S0

lk

100 td,ns

A В

F i g . 2 . D e l a y t i n e fcd d e p e n d e n c e on v o l t a g e . A : n - r e l a t i v e n u m b er o f f i r s t s t r e a m e r s w h ic h h a v e

d e l a y t i n e td ; N - m ean n u m b er o f s t r e a m e r s c r e a t e d b y a s i n g l e J f-r a y p u l s e . O n s e t p o t e n t i a l U0 = 7 . 6 2 kV. D a s h e d l i n e - s h a p e o f t h e J f-r a y p u l s e . В : Mean d e l a y t i m e t d d e p e n d e n c e on v o l t a g e .

U=7,62kV

N4*

\ ^ X f a y

100

J

tj.ns

1=4091«,

N-1.6

100 A

*d.n *

F i g . 3 . A : D i s t r i b u t i o n o f d e l a y t i n e t d f o r d i f f e r e n t J f-r a y i n t e n s i t i e s . В : Mean d e l a y t i n e fcd d e ­ p e n d e n c e on J f-r a y i n t e n s i t y ; i n t e n s i t y I Q c o r ­ r e s p o n d s t o t h e c h a r g e d p a r t i c l e s c o n c e n t r a t i o n 1 0 7 cm- 3 p e r J f-r a y p u l s e . In a l l c a s e s t h e j i t t e r o f r i s much s m a l l e r t h a n t h a t o f < t d - r > .

p la s m a d e n s i t y .

F i g . 4 . D i f f e r e n t s t a g e s o f b u r s t p u l s e d e v e l o p n e n t . A - d e v e l o p n e n t o f f i r s t a v a l a n c h e s ; 6 г s t a g e o f o v e r l a p p i n g a v a l a n c h e s , n0 ( t ) - d e n s i t y o f e l e c t r o n s c r e a t e d b y an Х - г л у p u l s e ; С - p l a s n a l a y e r ; - D -s k e t c h o f d i -s t r i b u t i o n , a - n e a n v a l u e o f a ; d a s h e d l i n e i n i t i a l f i e l d ; s o l i d l i n e - b u r s t p u l s e s t a g e ; d o t t e d l i n e - s t e a d y s t a t e c o r o n a .

s p r e a d o v e r t h e e l e c t r o d e s u r f a c e . T he n a i n p a r t o f c h a r g e s a r e c r e a t e d i n a l a y e r o f 2 /c r t h i c k n e s s . ( a - n e a n v a l u e o f a in i o n i z i n g z o n e ) . As a d r i f t v e l o c i t y o f i o n s i s lo w , t h e a c c u m u l a t i o n o f p o s i t i v e s p a c e c h a r g e o c c u r s i n t h i s l a y e r . At a t n o s p h e r i c p r e s s u r e and f o r t h e u s e d p o i n t r a d i u s , an e x t e n d e d l a y e r o f s p a c e c h a r g e c a u s e s t h e d i n i n i s h i n g o f t h e f i e l d [ 1 0 ] . W h e r e a s t h e c o n c e n t r a t i o n o f t r i g g e r i n g e l e o t r o n s л0 n e a r t h e b o r d e r o f i o n i z i n g z o n e i n c r e a s e s t h e n , s t a r t i n g f r o n a m om ent g o v e r n e d b y c h a n c e a v a l a n c h e s w i l l o v e r l a p ( F i g . 4 B ) . I t c a u s e s f u r t h e r d i m i n i s h i n g o f t h e f i e l d . By t h a t r e a s o n t h e l o s s o f e l e c t r o n s in t h e l a y e r d u e t o d r i f t t o t h e a n o d e d e c r e a s e s . T h i s s t a g e o f d i s c h a r g e i s a l r e a d y o b s e r v a b l e in e x p e r i m e n t s and i t i s nam ed a s a b u r s t p u l s e .

In t h e c a s e o f J f-r a y p r e i o n i z a t i o n t r i g g e r i n g , e l e c t r o n s a r e c r e a t e d h o m o g e n e o u s ly n e a r t h e p o i n t , and s e v e r a l p a r a l l e l a v a l a n c h e s w i l l d e v e l o p t o w a r d s a n o d e and t h e i r c o n ­ c e n t r a t i o n n 0 r i s e s l i n e a r l y i n t i m e . I f t h e J f-r a y i n t e n s i t y i s h i g h , t h e s t a g e a i s a b s e n t an d fcd v a r i e s w i t h i n n a r r o w l i m i t s ( F i g . 3 ) . 1 0 - f o l d d e c r e a s e o f i n t e n s i t y l e a d s t o t h e i n c r e a s e o f j i t t e r t d , t h e d e n s i t y o f n a i s t o o lo w f o r o v e r l a p p i n g o f a v a l a n c h e s and t h e c o n d i t i o n s o f i o n i z a t i o n a r e s i m i l a r t o a s i n g l e e J e c t r o n i n i t i a t i o n . T he l a s t s V a g e

( b u r s t p u l s e s t a g e ) i n p la s m a f o r m a t i o n i s p r e s e n t e d in

s t r e a n e r d e v e l o p n e n t w a s f i x e d .

( I V ) I n t h i s p a p e r b u r s t - t o - s t r e a n e r t r a n s i t i o n o c c u r s o n l y f o r r < 3 0 n s ( P i g . 2 B ) , i . e . o n l y w hen t h e f i e l d s t r e n g t h i n p l a s n a i s h i g h and s o t h e p r o b a b i l i t y t h a t i o n i ­

z a t i o n i n s t a b i l i t y n a y d e v e l o p e i s h i g h t o o .

R e f e r e n c e s

1 . L a a n , M ., P a r i s , P . P e r e l y g i n , V. L a s e r - a s s i s t e d s + r e a n e r d e v e l o p n e n t / / A b s t r a c t s o f i n v i t e d t a l k s an d c o n t r . p a p ers-E S C A H P IG 9 0 - O r l e a n s - 1 9 9 0 . - P . 3 7 1 - 3 7 2 .

2 . L e v a t t e r , J . S . , S a n d s t r o n , R . L . , M o r r i s , J . K . T h e c o r o -n a - p l a s -n a c a t h o d e : a -new l o -n g - l i f e e - b e a -n s c a t h o d e f o r J f-r a y p r e i o n i z a t i o n / / 4 JEEE P u l s e d p o w e r C o n f . ( A l b u q u e r q u e , N .M .,

1 9 8 3 ) . - D i g . t e c h n . P a p . - N .Y . - 1 9 8 3 . - P . 7 5 5 - 7 5 7 .

3 . K o r g e , H ., L a a n , M ., P a r i s , P . On f o r m a t i o n o f n e g a ­ t i v e c o r o n a p u l s e / / J . P h y s . D: A p p l. P h y s . - in p r i n t .

4 . L o e b , L .B . E l e c t r * o a l c o r o n a s . - B e r k e l e y ; L o s A n g e l e s : U n i v . o f C a l i f . P r e s s - 1 9 6 5 . - 6 9 4 p .

5 . R a e t h e r , H. E l e c t r o n a v a l a n c h e s and b r e a k d o w n in g a s e s - L o n d o n . - 1 9 6 4 .

6 . O m arov, O . A . , R u c h a d z e , A . A . , S c h n e e r s o n , G .A . On p la s m a m e c h a n ism o f h i g h p r e s s u r e g a s b r e a k d o w n in h i g h e l e c t r i c f i e l d / / S o v . J . T e c h n . P h y s . - 1 9 7 9 . - V. 4 9 . -P . 1 9 9 7 - 2 0 0 0 ( i n R u s s i a n ) .

7 . O m a ro v , O . A . , R u c h a d z e , A .A . E v i d e n c e o f p la s m a s t a g e o f a v a l a n c h e d e v e l o p m e n t i n c a s e o f s p a r k b r e a k d o w n / / S o v . J . T e c h n . P h y s . - 1 9 8 0 . - V. 5 0 . - P . 5 3 6 - 5 3 9 ( i n R u s s i a n ) .

8 . C h a r r i e r , J . , B o u l l o u d , A. P o s i t i v e G low C o r o n a D i s ­ t r i b u t i o n o f L i g h t E m i s s i o n in P o i n t - t o - P l a n e Gap / / 8 t h . I n t . C o n f . G as D i s c h a r g e s - O x f o r d , 1 9 8 5 . - P . 1 9 5 - 1 9 8 .

9 . M orrow , R ., L o w k e, J . J . S p a c e - c h a r g e e f f e c t s and d r i f t d o m in a t e d e l e c t r o n and p la s m a m o tio n / / J . P h y s . D: A p p l.

P h y s - 1 9 8 1 , - V. 1 4 , - P . 2 0 2 7 - 2 0 3 4 .

1 0 . S ig m o n d , R . S . , G o ld m a n , M. C o r o n a d i s c h a r g e p h y s i c s and a p p l i c a t i o n / / E l e c t r i c a l b r e a k d o w n and d i s c h a r g e in g a s e s . - N. Y. and L o n d o n : NATO, 1 9 8 3 . - P . 1 - 6 4 .

1 1 . P a r i s , P . I n v e s t i g a t i o n o f s t r e a m e r c h a r a c t e r i s t i c s on c o m b in e d v o l t a g e s ( D . C . + p u l s e v o l t a g e ) / / T a r t u D ip lo m a T h e s i s . - 1 9 7 8 - ( i n E s t o n i a n ) .

ИНИЦИИРОВАНИЕ СТРИМЕРА ИМПУЛЬСОМ РЕНТГЕНОВСКОГО ИЗЛУЧЕНИЯ

М. Л а а н , П. П арис

Р езю м е

Целью р а б о т ы я в л я л о с ь и с с л е д о в а н и е ф ор м и р о в а н и я с т р и м е р а в с и л ь н о н е о д н о р о д н о м р а з р я д н о м п р о м е ж у т к е о с т р и е - п л о с к о с т ь . Р а з р я д и н и ц и и р о в а л и при пом оци и м п у л ь с о в р е н т г е н о в с к о г о и з л у ­ ч е н и я ( с р е д н я я э н е р г и я к в а н т а - 5 к э В , д л и т е л ь н о с т ь и м п у л ь са - 1 4 0 н е ) . Р е н т г е н о в с к и й и м п у л ь с с о з д а в а л в в о з д у х е 1 0 7 с м - 3 за р я ж е н н ы х ч а с т и ц . И зм е р е н о в рем я ф ор м и р ован и я р а з р я д а в з а ­ в и с и м о с т и о т и н т е н с и в н о с т и и з л у ч е н и я при р а зн ы х н а п р я ж е н и я х . Н а й д е н о , ч т о д л я ф ор м и р о ва н и я с т р и м е р а н е о б х о д и м о с у щ е с т в о в а - в а н и е п л а з м е н н о г о с л о я в б л и зи о с т р и я

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THE MULTI-AVALANCHE NATURE OF STREAMER

Im Dokument PULSES INITIATION OF CORONA "V*?чV*- (Seite 85-98)