This research was sponsored by the National Science Foundation Grant NSF PHy 87-1440

Caskey, G.

Chant, N.S.

Friesel, D.L.

Galonsky, A.

Khazaie, F.

Nadasen, A.

Remington, B.

Schwandt, P.

Wakeland, R.S.

Wang, C.

Warner, R.E.

Yang, J.Q.

English

IUScholarWorks

KNOCKOUT KEACTIONS 
THE NON-COPLANAR 6 ~ i ( p , p d ) 4 ~ e  REACTION AT 120 and 200 MeV 
R.E. Warner, and R. S. Wakeland 
Obe r l i n  Col lege ,  Ober l in ,  Ohio 44074 
J*. Yang, D.L. F r i e s e l ,  and P. Schwandt 
Ind i ana  Un ive r s i t y  Cyclo t ron  F a c i l i t y ,  Bloomington, Indiana  47405 
N.S. Chant, F. Khazaie, and C. Wang 
U n i v e r s i t y  of Maryland, Col lege  Park, Maryland 20742 
G. Caskey, A. Galonsky, and B. Remington 
Michigan S t a t e  Un ive r s i t y ,  Eas t  Lansing,  Michigan 48824 
A. Nadasen 
U n i v e r s i t y  of Michigan, Dearborn, Michigan 48128 
Knockout r e a c t i o n s ,  i n t e r p r e t e d  through t h e  p a r t i c i p a n t s  a r e  i n s e n s i t i v e  t o  4. Thus, t h e  observed 
D i s t o r t e d  Wave Impulse Approximation (DWIA), p rov ide  s t r u c t u r e  i s  a t t r i b u t a b l e  t o  t he  momentum wave f u n c t i o n  
i n fo rma t ion  about c l u s t e r  p r o b a b i l i t i e s  and momentum r a t h e r  than  f i n a l - s t a t e  i n t e r a c t i o n s ,  changes i n  t he  
d i s t r i b u t i o n s .  Non-coplanar knockout s t u d i e s  a r e  two-body c r o s s  s e c t i o n ,  o r  vary ing  e f f e c t s  due t o  
p a r t i c u l a r l y  i n t e r e s t i n g  s i n c e ,  f o r  i n c r e a s i n g  ang l e  4 d i s t o r t i o n .  
between the  p a r t i c i p a n t  (de t ec t ed )  c l u s t e r  and t he  The 120 MeV d a t a  a r e  now publ ished and an a n a l y s i s  
p l a n e  of t h e  i n c i d e n t  and s c a t t e r e d  p r o j e c t i l e ,  they  of t h e  200 MeV d a t a  has been submit ted  f o r  
sample monotonica l ly  i n c r e a s i n g  s p e c t a t o r  c l u s t e r  pub l i ca t i on .  Measured energy-sharing s p e c t r a  f o r  
momenta. I n  t h e  p r e sen t  exper iments ,  s c a t t e r i n g  e i g h t  non-coplanari ty ang l e s  $I a r e  shown i n  Fig. 1, f o r  
geome t r i e s  a r e  used i n  which t h e  e f f e c t i v e  s c a t t e r i n g  Eo=200 MeV and a p a r t i c u l a r  q u a s i - e l a s t i c  po l a r  ang l e  
a n g l e  and f i n a l - s t a t e  r e l a t i v e  energy of t he  two p a i r .  Spec t r a  p r e d i c t e d  by t h e  DWIA, us ing  o p t i c a l  
F igu re  1. Cross s e c t i o n s  vs. deu t e ron  
l a b  energy f o r  t h e  6 ~ i ( p , p d ) 4 ~ e  
r e a c t i o n  a t  Eo=200.2 MeV and t h e  
q u a s i f  r e e  ang l e  p a i r  Op/Od=54 O/-48. go, 
f o r  e i g h t  va lues  of t h e  noncop lana r i t y  
a n g l e  4. Curves a r e  from M I A  
c a l c u l a t i o n s  w i th  d i f f e r e n t  
ground-s ta te  c l u s t e r  wavefunctions,  as 
d e s c r i b e d  i n  t he  t e x t .  
f o r  t he  p tL i ,  &a, and p t a  sys tems f o r  
t h e  n e a r e s t  a v a i l a b l e  e n e r g i e s  t o  those  a p p r o p r i a t e  t o  
o u r  experiment a r e  shown by s o l i d  l i n e s .  The 
ground-s ta te  c l u s t e r  wavefunction was t h a t  of a 
Woods-Saxon p o t e n t i a l  of r a d i u s  1.85 fm. The dashed 
c u r v e s  r e p r e s e n t  c a l c u l a t i o n s  wi th  t h e  o p t i c a l  
p o t e n t i a l  parameters  used f o r  t he  120 MeV a n a l y s i s ;  
t hey  i l l u s t r a t e  t he  i n s e n s i t i v i t y  of t h e  f i t s  t o  t he  
p o t e n t i a l  parameters.  
The y i e l d s  a t  120 and 200 MeV, i n t e g r a t e d  over  
d e t e c t e d  deuteron  energy ranges  of 11 and 20 MeV 
r e s p e c t i v e l y ,  a r e  p l o t t e d  vs. 41 i n  Fig.  2. F i t s  
ob t a ined  wi th  d i f f e r e n t  ground-s ta te  c l u s t e r  
wavefunct ions  a l s o  a r e  shown. A l l  of them unde rp red i c t  
10 
' ~ i  (p, pd) a 
2 1 . 9 ~ E ~ ~ 3 2 . 9  MeV 
\* E,= 120 MeV 
0.1 
/--.. I: ))s \.i 
F i g u r e  2. Cross s e c t i o n s ,  i n t e g r a t e d  over  de t ec t ed  
deu t e ron  energy,  vs.  41 a t  120 and 200 MeV bombarding 
energy.  Curves a r e  f o r  DWIA c a l c u l a t i o n s  wi th  
d i f f e r e n t  ground-s ta te  c l u s t e r  wavefunctions,  a s  
d e s c r i b e d  i n  t h e  t e x t .  
t h e  la rge-angle  y i e l d ,  i n d i c a t i n g  e i t h e r  an abundance 
of high-momentum components i n  t he  ground-s ta te  
wavefunction o r  t h e  presence  of  r e a c t i o n  mechanisms 
( o t h e r  than  f i r s t - o r d e r  q u a s i e l a s t i c  s c a t t e r i n g )  whose 
y i e l d  is more n e a r l y  i s o t r o p i c .  The so f t - co re  
wavefunction5 comes c l o s e s t  t o  reproducing  t h e  la rge-  
a n g l e  y i e l d  but g e n e r a t e s  unphys i ca l l y  l a r g e  ( ~ 1 . 2 5 )  
s p e c t r o s c o p i c  f a c t o r s  (Cd's) .  The Woods-Saxon 
p o t e n t i a l  p r e d i c t s  minima a t  both  ene rg i e s ;  one i s  
observed a t  120 MeV but no t  (w i th  s t a t i s t i c a l  
s i g n i f i c a n c e )  a t  200 MeV. Cdls  f o r  t h i s  p o t e n t i a l  a r e  
0.76 and 0.84, r e s p e c t i v e l y ,  a t  t h e s e  ene rg i e s .  
F i n a l l y ,  c a l c u l a t i o n s  were done a t  200 M e V  f o r  a 
recent ly-publ ished6 wavef unc t i o n  ob t a ined  by s o l u t i o n  
of  t h e  Faddeev equat ions .  The p red i c t ed  y i e l d  vs. @ i s  
n e a r l y  i d e n t i c a l  t o  t h a t  of t h e  Woods-Saxon p o t e n t i a l ,  
and t h e  deduced Cd (0.76) compares f avo rab ly  w i th  t h e  
v a l u e s  of 0.70 t o  0.75 obta ined  by Kukulin e t  a1.6 f o r  
t h e i r  s i x  d i f f e r e n t  models. 
1 )  R.E. Warner e t  a l . ,  Nucl. Phys. A422, 205 (1984); 
submit ted  t o  Nucl. Phys. 
2)  G.R. S a t c h l e r  and R.M. Haybron, Phys. L e t t .  2, 
313 (1964). 
3) B. Ta t i s che f f  and I. Br issaud,  Nucl. Phys. A155, 89 
(1 970). 
4)  V. Comparat e t  a l . ,  Phys. Rev. C 12, 251 (1975). 
5 )  J. Janecke e t  a l . ,  Nucl. Phys. A343, 16  (1980). 
6)  V.I. Kukulin e t  a l . ,  Nucl. Phys. A417, 128 (1984). 


The Non-coplanar 6-Li(p,pd)4-He Reaction at 120 and 200 MeV

https://scholarworks.iu.edu/dspace/bitstream/2022/1119/1/iucf_1984_113-114.pdf

The Non-coplanar 6-Li(p,pd)4-He Reaction at 120 and 200 MeV

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