ANP PROJECT QUAH'TERLY PROG i n n e r l a y e r by t h e 5 / 1 6 - i n . B o r a l sheet, The d a t a f o r t h e t r a v e r s e s t h r o u g h t h e c o m p o s i t e r e f l e c t o r when t h e Bora1 s t r i p s were p r e s e n t i n t h e t e s t c e l l s are given i n F i g , 17. Curve 1 i s the bare-indium a c t i v a t i o n , curve 2 s h o w s t h a t o b t a i n e d f o r t h e cadmium c o v e r e d i n d i u m , and c u r v e 3 shows t h e d i f f e r e n c e b e t w e e n c u r v e s 1 and 2 . A l l d a t a were p l o t t e d a s a f u n c t i o n o f t h e d i s t a r l c e from t h e o u t s i d e o f t h e t e s t section. S i m i l a r t r a v e r s e s w e r e made '* w i t h t h e B o r a l s t r i p s o m i t t e d and t h e s p a c e l e f t empty. F i g u r e 1 8 shows t h e b a r e - i n d ium and c a d miurn- c o v e r e d i nd i um a c t i v a t i o n s and t h e i r d i f f e r e n c e p l o t t e d a l s o as a function of t h e d i s t a n c e from t h e o u t s i d e o f t h e t e s t s e c tion.
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DISi-ANCE FROM OUTSIDE OF REFLECTOR (in.)
F i g . 18. Bare a n d Cadmium-Covered Indium Traverses Through S t a i n l e s s S t e e l - P l e x i g l a s Cooiposi t e R e f l e c t o r .
DISTANCE FROM OUTSIDE OF REFLECTOR (in )
F i g . 17, Barr a n d Cadmium-Covered In d i urn Tr a v e r s e s T h r c) u g h S t a i n 1 e s s S t e e l - P l e x i g l a s - B o ra I C o m p o s i t e Re f 1ec to r.
Poison Rod C a l i b r a t i o n s . A m e a s u r e m e n t was made o f t h e r e a c t i v i t y d e p r e s s i o n by e a c h o f t h r e e b o r o n c a r b i d e r o d s f u r n i s h e d by t h e G e n e r a l E l e c t r i c Co. f o r t e s t a s p o i s o n c o n t r o l r o d s . The r u d s were 1 / 2 i n . i l l d i a m e t e r a n d a b o u t 36 i n . l o n g and d i f f e r e d s l i g h t l y i n i n t e r n a l s t r u c t u r e ; one contained a p l a s t i c insert within the b o r o n c a r b i d e and t h e o t h e r c o n t a i n e d aluminum. The l o s s i n r e a c t i v i t y i n c u r r e d by s u b s t i t u t i n g t h e p o i s o n f o r p l a s t i c within t h e r e a c t o r w a 6 found t o b e a b o u t 20 c e n t s ( 3 ) a t t h e c e n t e r o f t h e c o r e a n d a b o u t 11 c e n t s a t t h e . .~. ~
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(3)One hundred c e n t s i s a r e a c t i v i t y change e q u i v a l e n t t o t h e e f f e c t i v e fraction o f d e l a y e d neutrons.