Test of theSU 3 breaking in inclusive electroproduction of hadrons

The m e a s u r e m e n t of s ing le -had ron d i s t r i b u t i o n s in deep ine las t ic (i) r eac t ions can serve as a usefu l too l for t h e u n d e r s t a n d i n g of t he s t r u c t u r e of t h e nucleon. The quarkp a r t o n mode l as desc r ibed b y FEYNMAN a n d BEn~AN et al. (2) ha s more p r e d i c t i v e power t h a n t h e l i g h t c o n e a p p r o a c h (a) for p r o d u c t i o n of single h a d r o n s in t he c u r r e n t f ragm e n t a t i o n region. I n th i s p a p e r t h e t w o c o m p o n e n t (4) d u a l i t y idea is be ing app l ied w i t h i n t h e p a r t o n mode l to descr ibe t h e deep ine las t ic r eac t ions . The q u a r k d i s t r ibu t i on w i t h i n t h e nuc l eon is d i v i ded i n t o two c o m p o n e n t s such as t h r e e va lence qua rks p lus a core of q u a r k a n t i q u a r k pa i rs . T he sea of core q u a r k s is a s sumed to be composed of equa l n u m b e r s of each type . Th i s co r responds to t h e p o m c r o n b a c k g r o u n d p a r t of t h e a m p l i t u d e . The t h r e e v a l e n c e q u a r k c o m p o n e n t co r re sponds to t h e Regge r e s o n a n t p a r t of t h e a m p l i t u d e . The n u m b e r of t he p a r t o n d i s t r i b u t i o n f u n c t i o n s can be r e d u c e d to one on ly i f one assumes t h e k i n d e r g a r t e n p a r t o n mode ls of BJOI~KEN (5). I sosp in a n d cha rge c o n j u g a t i o n i n v a r i a n c e reduces t h e n u m b e r of p a r t o n f r a g m e n t a t i o n f u n c t i o n s to t h ree . W e also define V(z) (s) as a f a v o u r e d t o u n f a v o u r e d f r agment a t i o n r a t i o such t h a t