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

Brown, J.D.

Cupps, V.R.

Foster, C.C.

Gering, J.A.

Jones, W.P.

Low, D.A.

Miller, D.W.

Nann, H.

Olmer, C.

Opper, A.K.

Schwandt, P.

Stephenson, E.J.

Wissink, S.W.

English

IUScholarWorks

TRANSFER REACTIONS 
A TEST OF THE COPLANAR AND FAR-SIDE FEATURES OF INTERMEDIATE ENERGY (d ,p )  REACTIONS 
V.R. Cupps, E.J. Stephenson, C.C. F o s t e r ,  J.A. Gering,  W.P. Jones ,  D.A. Low, 
D.W. M i l l e r ,  H. Nann, C. Olmer, A.K. Opper, P. Schwandt, S.W. Wissink 
Indiana  Un ive r s i t y  Cyclo t ron  F a c i l i t y ,  Bloomington, Indiana  47405 
J .D .  Brown 
P r ince ton  Un ive r s i t y ,  P r ince ton ,  New J e r s e y  08544 
R.C. Johnson and J.A. Tos t ev in  
Un ive r s i t y  of Surrey ,  Gui ldford ,  Surrey ,  United Kingdom 
During t he  a n a l y s i s  of our d a t a  from t h e  t h e  a t t r a c t i v e  p a r t s  of t he  r e a l  c e n t r a l  and r e a l  sp in-  
1 1 6 ~ n ( d , p ) 1 1 7 ~ n  r e a ~ t i o n l * ~  a t  Ed = 79 MeV, we observed o r b i t  p o t e n t i a l s .  
d a t a  t r ends  which convent ional  DWBA could not  2. The neut ron  i s  s t r i p p e d  i n t o  an  o r b i t  t h a t  i s  
reproduce.  I n  an a t tempt  t o  improve agreement wi th  coplanar  wi th  t h e  asymptot ic  r e a c t i o n  plane.  S t a t e d  
experiment s e v e r a l  f e a t u r e s  were added t o  t h e  DWBA, ano the r  way, t h e  r e c o i l  nuc l ea r  s t a t e  i s  popula ted  by 
v i z .  an a d i a b a t i c  p r e s c r i p t i o n  f o r  t h e  deuteron  only  one p r o j e c t i o n  of t h e  neut ron  angu la r  momentum, 
s c a t t e r i n g  wavefunction3 ( h e r e a f t e r  r e f e r r e d  t o  a s  ADWA mn = In, when t h e  q u a n t i z a t i o n  a x i s  is pe rpend icu l a r  t o  
c a l c u l a t i o n s ) ,  a  f i n i t e  range t rea tment  of both t h e  t h e  r e a c t i o n  p lane .  
deuteron  S- and D-  state^,^ matched en t r ance  and e x i t  3 .  There is very l i t t l e  s p i n  f l i p  i n  e i t h e r  t h e  
channel  geometr ies ,  and non - loca l i t y  c o r r e c t i o n s  .5 en t r ance  o r  e x i t  channel.  
Ca l cu l a t i ons  i nco rpo ra t i ng  a l l  of t he se  changes were When a l l  of t h e s e  c h a r a c t e r i s t i c s  a r e  s t r i c t l y  
made u s ing  t h e  program T W O F N R , ~  and i t  was found t h a t  t r u e ,  it can be shown t h a t  only two r e a c t i o n  ampl i tudes  
t h e s e  e x t r a  f e a t u r e s  d id  produce s i g n i f i c a n t  s u r v i v e  f o r  j = 1-112 neut ron  coupl ing .  Thus a l l  s p i n  
improvements i n  t h e  agreement between D i s t o r t e d  Wave observables  a r e  redundant and va r ious  l i n e a r  
c a l c u l a t i o n s  and t h e  1 1 6 ~ n ( d , p ) 1 1 7 ~ n  da t a .  However combinations of t h e  ana lyz ing  powers w i l l  vanish ,  
agreement of t h e  ADWA c a l c u l a t i o n s  w i th  d a t a  f o r  t h e  thereby gene ra t i ng  va r ious  r e l a t i o n s h i p s  among t h e s e  
j = 1-112, 7/2+, 0.712 MeV t r a n s i t i o n ,  p a r t i c u l a r l y  t h e  s p i n  observables  which can be t e s t e d  a g a i n s t  
Ayy t e n s o r  ana lyz ing  power, remained very  poor. experiment.  One such r e l a t i o n s h i p ,  Ay = -(2+Ayy)/3, 
I n  an  a t tempt  t o  unders tand t h e  disagreement was t e s t e d  a g a i n s t  our 1 1 6 ~ n ( d , p ) 1 1 7 ~ n  (7/2+,0.712) 
between exper imenta l  d a t a  and D i s t o r t e d  Wave d a t a  i n  Fig.  1. The h igh  degree t o  which t h e  model 
c a l c u l a t i o n s  f o r  t h i s  well-matched t r a n s i t i o n ,  we fo l l ows  t h e  above c h a r a c t e r i s t i c s  is suppor ted  by t h e  
a t  tempted t o  i d e n t i f y  t h e  dominant c h a r a c t e r i s  t i c s  of obse rva t i on  t h a t  t h e  c a l c u l a t e d  va lue  of Ay + (2+Ayy)/3 
t h e  ADWA c a l c u l a t i o n  and f i n d  ways t o  confirm them is  l e s s  than  0.1 f o r  a  f u l l  D i s t o r t e d  Wave c a l c u l a t i o n  
exper imenta l ly .  When t h e  angu la r  momentum t r a n s f e r  is us ing  only  t h e  deuteron  S-s ta te .  However t h e  d a t a  
l a r g e ,  t h e  c h a r a c t e r i s t i c s  a r e  : sugges t s  a  s u b s t a n t i a l  breaking  of t he se  r u l e s .  
1. The c r o s s  s e c t i o n  is  dominated by c o n t r i b u t i o n s  We f i r s t  cons idered  t h e  p o s s i b i l i t y  of s i g n i f i c a n t  
from t h e  f a r  s i d e  of t he  nucleus  through t h e  a c t i o n  of s p i n - f l i p  i n  t h e  deuteron  channel.  Sp in - f l i p  
t h e s e  come from o t h e r  c o n t r i b u t i o n s  ( such  a s  breakup)  
1 I6 Sn (d ,p)  17sn (712') E d = 7 9  MeV 
Figu re  1. Exper imenta l  and c a l c u l a t e d  angu l a r  
d i s t r i b u t i o n s  of Ay and i t s  coun t e rpa r t  
% E -(A + 2 ) / 3  f o r  t h e  7/2+ t r a n s i t i o n  i n  t h e  
1 Y 6 ~ n ( d , ; J 1 1 7 ~ n  r e a c t i o n .  The bottom p o r t i o n  shows 
t h e  d i f f e r e n c e ,  Ay-Ay. The s o l i d  (dashed)  curves  
i n c l u d e  ( n e g l e c t )  t h e  deuteron  D-state.  
c o n t r i b u t i o n s  t o  Ay+(Ayy+2)/3 can o r i g i n a t e  i n  
s t r i p p i n g  from t h e  deuteron  D-s ta te ,  t en so r  f o r c e s  
between t h e  deuteron  and t h e  nucleus ,  and coup l i ng  t o  
breakup s t a t e s  w i th  r e l a t i v e  n-p angu l a r  momentum 
g r e a t e r  t han  zero .  Genera t ing  a  l a r g e r  s p i n - f l i p  
ampl i tude  by i n c l u d i n g  t h e  deuteron  D-state i n  our 
c a l c u l a t i o n s ,  a s  shown i n  Fig.  1, he lp s ,  but  it s t i l l  
does not  reproduce  t h e  da t a .  Add i t i ona l  c a l c u l a t i o n s  
sugges t  t h a t  t h e  t e n s o r  f o r c e  e f f e c t s  a r e  i n s i g n i f i c a n t  
f o r  t h i s  case.8 
There is c l e a r l y  a problem wi th  t he  D i s t o r t e d  Wave 
c a l c u l a t i o n s ,  and i t  is impor tan t  t o  r e s o l v e  whether 
t o  t h e  s p i n - f l i p  ampl i tude  o r  a  d e v i a t i o n  from one of 
t h e  o t h e r  two c h a r a c t e r i s t i c s .  It can be shown t h a t  
t h e  l i n e a r  combination py + (2Ayy+1)/3 is  s e n s i t i v e  t o  
only  ampl i tudes  where %#In ,  t hus  c o n s t i t u t i n g  a  
d i f f e r e n t  t e s t  of t h e  c a l c u l a t i o n .  
A comparison of t h e  outgoing  p o l a r i z a t i o n  and t h e  
Ayy t e n s o r  ana lyz ing  power can b e s t  be performed f o r  a  
c a s e  where t h e  j = 1-112 t r a n s i t i o n  connects  t h e  ground 
s t a t e s  of two s t a b l e  and r ea sonab ly  abundant i s o t o p e s .  
Then t h e  p o l a r i z a t i o n  may be measured by obse rv ing  t h e  
ana lyz ing  power i n  t h e  t ime r eve r sed  r e a c t i o n .  One 
such t r a n s i t i o n  is  t h e  512- ground s t a t e  r e a c t i o n  i n  
6 6 ~ n ( d , p ) 6 7 ~ n .  Thus s e l e c t e d  measurements of t h e  Ayy 
t e n s o r  ana lyz ing  power and t h e  outgoing  p ro ton  
p o l a r i z a t i o n  i n  t h e  6 6 ~ n ( d , p ) 6 7 ~ n ( 5 / 2 - , g . s .  ) r e a c t i o n  
a t  Ed = 88 MeV were made i n  t h e  s p r i n g  of 1985. The 
expe r imen t a l  method was i d e n t i c a l  t o  t h a t  o u t l i n e d  i n  
Ref. 9. A new c a l i b r a t i o n  of t h e  beam l i n e  2 
po l a r ime t e r  f o r  deuteron  e n e r g i e s  above 80 MeV i s  
de sc r i bed  i n  Ref. 10. The r e s u l t s  of t h e s e  
measurements a long  w i th  c a l c u l a t i o n s  i n c l u d i n g  t h e  
deu t e ron  D-state a r e  shown i n  F ig .  2. The c a l c u l a t i o n  
s e r i o u s l y  unde re s t ima t e s  t h e  measured va lue s  of 
py + (2Ay+1)/3, i n d i c a t i n g  t h a t  it obeys t h e  
c h a r a c t e r i s t i c s  g iven  p r e v i o u s l y  wh i l e  t h e  d a t a  does 
not .  
A forward  ang l e  o s c i l l a t i o n  p a t t e r n  (See Fig .  1 )  
p r e s e n t  i n  t h e  angu l a r  d i s t r i b u t i o n  measurements of t h e  
%n(d ,  p )  7 ~ n  r e a c t  i o n  was u s u a l l y  ab sen t  i n  t h e  
c a l c u l a t i o n s .  The o s c i l l a t i o n  pe r i od  sugges t s  t h a t  
t h e r e  a r e  comparable c o n t r i b u t i o n s  from both t h e  nea r  
and f a r  s i d e s  of t h e  nucleus ,  which would i n v a l i d a t e  
both  of t h e  f i r s t  two c h a r a c t e r i s t i c s  and p rov ide  a  
b a s i s  f o r  unde r s t and ing  t h e  v i o l a t i o n s  d e p i c t e d  i n  
F igs .  1 and 2. The momentum matching t h a t  makes c ro s s -  
6 6 Zn(d,p) 6 7 ~ n  ( 5 / 2 - )  Ed=88  MeV 
1 I I 1 I I 1 I I 
d e s c r i bed  i n  t h e  D i s t o r t e d  Wave model of t r a n s f e r  
r e a c t i o n s  i s  s u b s t a n t i a l l y  changed. The n a t u r e  of such 
F igu re  2. Exper imenta l  and c a l c u l a t e d  angu l a r  
d i s t r i b u t i o n s  f o r  t h e  outgoing  pro ton  p o l a r i z a t i o n  
py and i t s  coun t e rpa r t  Ty -(2Ayy + 1 ) / 3  f o r  t h e  
512- ground s t a t e  t r a n s i t i o n  i n  t h e  6 6 ~ n ( d , p ) 6 7 ~ n  
r e a c t i o n .  The bottom p o r t i o n  shows t h e  
d i f f e r e n c e ,  py-py. The curves  a r e  f u l l  D i s t o r t e d  
Wave c a l c u l a t i o n s .  
s e c t i o n s  f o r  t h e s e  s t a t e s  l a r g e  a l s o  overwhelms t h e  
much s m a l l e r  nea r  s i d e  c o n t r i b u t i o n .  Such a  nea r  s i d e  
a  change is c u r r e n t l y  unknown. 
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F o s t e r ,  W.P. Jones ,  D.W. M i l l e r ,  H. Nann, and P. 
Schwandt, IUCF S c i e n t i f i c  and Techn i ca l  Repor t ,  
(1983) ,  108-110. 
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F o s t e r ,  H. Nann, P. Schwandt, IUCF; J . W .  S eube r t ,  
IUPUI; J.A. Tos t ev in ,  Univ. of Surrey;  IUCF 
S c i e n t i f i c  and Techn i ca l  Repor t ,  111 (1983) 
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(1970).  
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Cupps, J .D .  Brown, C.C. F o s t e r ,  J.A. Ger ing ,  W.P. 
Jones ,  D.A. Low, D.W. M i l l e r ,  H. Nann, C. Olmer, 
A.K. Opper, P. Schwandt, J .W.  S eube r t ,  S.W. 
Wissink,  submi t ted  t o  Phys ics  L e t t e r s .  
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F o s t e r ,  W.P. Jones ,  D.W. M i l l e r ,  H. Nann, P. 
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c o n t r i b u t i o n  can be gene ra t ed  only  i f  t h e  phys i c s  


A Test of the Coplanar and Far-side Features of Intermediate Energy (d,p) Reactions

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A Test of the Coplanar and Far-side Features of Intermediate Energy (d,p) Reactions

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