This work was supported by National Science Foundation Grants PHY 76-84033A01, PHY 78-22774, and Indiana Universit

Baker, F. Todd

Jones, W.P.

Scott, Alan

Styles, R.C.

Wiggins, J.P. Jr.

English

IUScholarWorks

SPIN-ORBIT EFFECTS ON THE SHAPES OF CROSS SECTIONS I N  THE 9 0 ~ r ( p , p ' )  
REACTION AT 160 MeV 
Alan ~ c o t t * ,  F. Todd Baker*, W.P. Jones, J . D .  Wiggins, Jr. and 
R.c. s t y l e s k  
R e l a t i v i s t i c a l l y  correc ted  c o l l e c t i v e  model ca l -  I n  l a t e r  prel iminary DWIA ca l cu l a t i ons  f o r  t he se  t ran-  
cu l a t i ons  have now been completed1) f o r  t h i s  experi-  s i t i o n s  t o  (gg/2)2  proton s t a t e s  wi th  L=2, L=4, L=6 and 
ment, i n  which t h e  deformed-spin-orbit (DSO) def orma- L=8 (with t h e  f r e e  nucleon-nucleon G3Y f o r c e  used 
t i o n  parameter f3E0 was va r i ed  from a value much less e a r l i e r 2 )  and with only t h e  simple (g9/2)2  wave 
than the  f i xed  c e n t r a l  ( r e a l  and imaginary) parameter func t ions ) ,  Love f inds3)  t he  sp in-orbi t  c ros s  s e c t i o n  
f 3 ~  up t o  a va lue  much g r e a t e r  than BL; f o r  L=8 up t o  increas ingly  dominates t h e  c e n t r a l  p a r t  of t h e  fo rce  
f3E" = 8. OBL. Comparisons of these  ca l cu l a t i ons  were a s  t h e  L-transfer  increases ,  u n t i l  f o r  L=8 the  spin- 
made with measured c ros s  s ec t ions  f o r  t h e  L=3 t r a n s i -  o r b i t  c ros s  s ec t ion  is about 8 t imes l a r g e r  than the  
t i o n  t o  the  3- c o l l e c t i v e  s t a t e  a t  2.75 MeV, f o r  t h e  c e n t r a l  c ros s  sec t ion .  For t h i s  L=8 t r a n s i t i o n ,  Love 
L=5 t r a n s i t i o n  t o  t he  (p112, ggI2) s t a t e  a t  2.32 MeV f i n d s  t h e  c ros s  s ec t ion  f o r  t h e  tensor  fo rce  about 
and f o r  t h e  L=2, 4, 6, and 8 t r a n s i t i o n s  t o  t h e  (gg/2)2  h a l f  t h a t  f o r  t h e  c e n t r a l  p a r t  of t h e  force.  Core 
proton s t a t e s .  po l a r i za t ion  amplitudes need t o  be added t o  t hese  
Two c l e a r  f e a t u r e s  a r e  revealed i n  these  c o l l e c t i v e  DWIA ca l cu l a t i ons  with simple (gg/2) wave funct ions ,  
ca l cu l a t i ons ;  t h e  f i r s t  prominent maximum of t h e  DSO s ince  Love was requi red  t o  mul t ip ly  h i s  o v e r a l l  c ros s  
p a r t i a l  c ross  s e c t i o n  a lone  is always a t  a  s i g n i f i c a n t l y  s e c t i o n  by a f a c t o r  of 10 t o  match t h e  da t a  f o r  t h e  
l a r g e r  angle  than the  maximum of t h e  c e n t r a l  p a r t i a l  L=4 t r a n s i t i o n ,  by a f a c t o r  of 3 f o r  t h e  L=6 c ros s  
c ros s  s ec t ion  alone (with r e a l  and imaginary components, s ec t ion ,  and by a f a c t o r  of 2 f o r  t he  L=8 t r a n s i t i o n .  
and Coulomb e x c i t a t i o n  where necessary),  and secondly A manuscript descr ib ing  these  major e f f e c t s  of 
t he  subs id iary  maxima and minima of t he  DSO c ros s  t he  sp in-orbi t  ampli tudes is i n  f i n a l  prepara t ion ,  
s ec t ion  a r e  out  of phase wi th  those of t h e  c e n t r a l  which w i l l  s h o r t l y  be submitted f o r  publ ica t ion .  
c ross  s ec t ion  f o r  each t r a n s i t i o n .  These two f e a t u r e s  
s e n s i t i v e l y  prevent  a  good f i t  t o  the  shape of each *The Univers i ty  of ~ e o r ~ i a ,  Athens. 
measured c ros s  s e c t i o n  except f o r  a  narrow range of 1. A. Sco t t ,  unpublished. 
t he  r a t i o  f3Zo/BL. The b e s t  f i t s  f o r  t h e  sequence of 2. W.G. Love, Alan Sco t t ,  F. Todd Baker, W.P. Jones 
and J .D.  Wiggins, Jr., Phys. Le t t .  73B (1978) 277. 
(gq 12)" s t a t e s  r equ i r e  increas ing  DSO con t r ibu t ions  a s  
--, - 
3. W.G. Love, Conference on t h e  (p,n) Reaction and 
the  L-transf e r  increases ;  f o r  L=4 f3z0 = 1. 25B4 ( c e n t r a l ) ,  Nucleon-Nucleon Forces, Te l lu r ide ,  March 29-31, 
1979, t o  be published. 
and f o r  t h e  L=6 and L=8 t r a n s i t i o n s  t h e  DSO cross  sec- 
t i o n s  alone y i e l d  good f i t s  t o  t he  da t a  shapes. The 
f i t  t o  t he  c ros s  s e c t i o n  f o r  t h e  3- s t a t e  a t  2.75 MeV 
requ i r e s  f3;O = 1.5fi3(central) ,  and t h e  f i t  t o  t h e  c ros s  
s e c t i o n  f o r  t h e  L=5 t r a n s i t i o n  t o  t h e  ( ~ ~ / ~ , g ~ / ~ )  
proton s t a t e  a t  2.32 MeV requ i r e s  f3gO = 2.9B5(central). 


Spin-Orbit Effects on the Shapes of Cross Sections in the 90-Zr(p,p') Reaction at 160 MeV

https://scholarworks.iu.edu/dspace/bitstream/2022/2926/1/iucf_1978_38.pdf

Spin-Orbit Effects on the Shapes of Cross Sections in the 90-Zr(p,p') Reaction at 160 MeV

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