SOBRE LA TEORÍA DEL ACCESO HISTÉRICO

tion phase

X horizontal

the l a t t e r w o u l d receive r e f l e c t e d r a d i a t i o n from a w i d e r angle in the h o r i z o n t a l p l a n e than w o u l d the

v e r t i c a l p o rts in a vertical plane. W h i l e it is p o s s i b l e t h a t the d i f f e r e n c e s b e t w e e n the v e r t i c a l and the

h o r i z o n t a l s i gnals shown in Fig. 5.2, w e r e due in p a r t to c o m p o n e n t s of r e f l e c t e d r a d i a t i o n , so m a n y o t h e r f a c t o r s are i n v o l v e d that no d e f i n i t e c o n c l u s i o n s can be dra w n . D i f f e r e n c e s in signal v a l u e s w o u l d be e x p e c t e d of c o urse, even if both sets of p o r t s c o i n c i d e d in cf> , e x c e p t for p a r t i c u l a r plasma d i s t r i b u t i o n s .

In Fig. 5.3, i n t e n s i t y d i s t r i b u t i o n s at 278.1 nm are shown, (a) for v e r tical ports and (b) for h o r i z o n t a l p o r t s , at 10 y s inte r v a l s about a spike. In Fig.

5.3(c) the same indi v i d u a l values as in (b) w e r e p l o tted, but the cur v e s w e r e drawn to o b t a i n a m o r e s y m m e t r i c a l d i s t r i b u t i o n a b out a point b e t w e e n H3 and H 4 . That it is p o s s i b l e to o b t a i n such d i f f e r e n t c u r v e s from the same set of v a l u e s h i g h l i g h t s the n e e d for m e a s u r e m e n t s w i t h s m a l l e r i n t e r v a l s of d i s t a n c e b e t w e e n a d j a c e n t o b s e r v i n g points.

For o b t a i n i n g i n f o r m a t i o n on the p l a s m a b e h a v i o u r due to e f f e c t s of the applied fields, m e a s u r e m e n t s w e r e m a d e for bo t h d i r e c t i o n s of B and for d i f f e r e n t m a g n i t u d e s

<P

of and also for d i f f e r e n t m a g n i t u d e s and d i r e c t i o n s of Bj^ . In se c t i o n 5.2, a dis c u s s i o n , of the eff e c t s of these a p p l i e d fields on the plasma b e h a v i o u r , is given. In

s e c t i o n s 5.3 and 5.4 the e s t i m a t i o n of e l e c t r o n t e m p e r a t u r e and the e s t i m a t i o n of oxygen ion d e n s i t y are r e s p e c t i v e l y d i s c u s s e d . F i n a l l y in section 5.5, some c o n c l u s i o n s are d r a w n .

Fig. 5-3(a)