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

Clausen, B.L.

Jacobs, W.W.

Kraushaar, J.J.

Lindgren, R.A.

Nann, H.

Peterson, R.J.

Plumley, M.A.

Roman, S.

English

IUScholarWorks

PROTON STRIPPING TO STRETCHED STATES I N  2 6 A l ,  5 2 ~ r  and 6 0 ~ i  
R.J. Peterson,  B.L. Clausen and J.J. Kraushaar 
Un ive r s i ty  of Colorado, Boulder, Colorado 80309 
R.A. Lindgren and M.A. Plum 
Unive r s i ty  of Massachusetts,  Amherst, Massachusetts 01003 
W.W. Jacobs ,  8. Nann and S.  oma an+ 
Ind iana  Un ive r s i ty  Cyclotron F a c i l i t y ,  Bloomington, Indiana 47405 
The s t r e t c h e d  s t a t e s  of h ighes t  angular  momentum coherent  ( s c a t t e r i n g )  and incoherent  ( s t r i p p i n g )  
of an  even-mass t a r g e t  formed by a pa r t i c l e -ho le  e x c i t a t i o n  of these  simple s t r e t c h e d  s t a t e s .  A 
combination a r e  a c c e s s i b l e  by both i n e l a s t i c  s c a t t e r i n g  t h e o r e t i c a l  framework based on the  Nilsson scheme has 
and charge exchange r e a c t i o n s ,  o r  by s i n g l e  nucleon i n  f a c t  been developed.5 For 60~ i ,  e l e c t r o n  s c a t t e r i n g  
s t r i p p i n g  onto the  appropr i a t e  odd-mass t a r g e t .  We d a t a  e x i s t 6  t o  permit t h i s  comparison f o r  a wide a r r a y  
have populated the  6' s t a t e s  of 26Al from the  5/2+ of 8' s t a t e s ,  while f o r  5 2 ~ r ,  new e l e c t r o n  s c a t t e r i n g  
ground s t a t e  of 25&43 by £712 pro~ton s t r i p p i n g .  
S i m i l a r l y ,  t he  8' s t a t e s  of 5 2 ~ r  and 6 0 ~ i  were
r e s u l t s  a r e  c u r r e n t l y  being analyzed.7 
We used the  ( a , t )  s t r i p p i n g  r e a c t i o n  a t  a beam 
populated by gg/2 proton s t r i p p i n g  on the  712' ground energy of 80 MeV t o  enhance the  popula t ion of t h e  high 
s t a t e s  of 5 1 ~  and 5 9 ~ o ,  r e spec t ive ly .  The s t a t e s  of s p i n  s t a t e s .  Sample s p e c t r a  f o r  2 6 A l  and 6 0 ~ i ,  wi th  an  
2 6 ~ 1  a r e a l s o  a c c e s s i b l e  by the  26Mg(p,n)26~1 reac t ion ,  i n s t rumen ta l  r e s o l u t i o n  of 90 keV, obta ined with the  
and t h e i r  T-1 analogs  have been s tud ied  by 26Mg ( p , p l ) l  QDDM spectrometer  system, a r e  shown a s  Figs.  I and 2. 
and ( e , e ~ ) . ~  For 6 0 ~ i ,  the  known 8' s t a t e s 6  a r e  ind ica t ed ;  a s  
S imi l a r  s t u d i e s  of s c a t t e r i n g 3  and nucleon expected, t h e  ( a , t )  r e a c t i o n  has s e l e c t i v e l y  emphasized 
t r a n s f e r  r eac t ions4  t o  the  6' s t a t e s  i n  A=28 have been these  s t a t e s  even a t  very  high e x c i t a t i o n  energies .  
repor ted .  Whereas 2 8 ~ i  e x h i b i t s  but one s t rong  For 26~1, the peaks corresponding t o  the  T=1 analog 
6' s t a t e  of each i sosp in ,  T=O and P L ,  a  broader a r r ay  6' s t a t e s L  i n  26Mg a r e  noted, wi th  our measured 
of T=l 6- l e v e l s  is  known f o r  A=26. Th i s  permits  a e x c i t a t i o n  energies .  Angular d i s t r i b u t i o n s  f o r  t hese  
more i n t e r e s t i n g  t e s t  of the comparison between s t a t e s  i n  2 6 ~ 1  have been analyzed, and comparison t o  
momen tum 
Figure  1. A composite momentum spectrum f o r  the  2 5 & ( a , t ) ~ l  r e a c t i o n  is shown on a square  r o o t  s ca l e .  E x c i t a t i o n  
e n e r g i e s  a r e  shown f o r  the  s t a t e s  ass igned s p i n s  of 6' from the  p resen t  work o r  from previous d a t a  ( see  t ex t ) .  
Figu re  2. A composite momentum spectrum f o r  t h e  5 9 ~ o ( a , t ) 6 0 ~ i  r e a c t i o n  is  shown. S t a t e s  w i th  8' s p i n  assignment 
from e l e c t r o n  s c a t t e r i n g  d a t a  a r e  i n d i c a t e d  and s epa ra t ed  i n t o  T=2 and -3 regions .  
cn 
+- 
C 
3 
DWBA p r e d i c t i o n s  and t o  t h e  known 712' t r a n s f e r  on a 
24Mg t a r g e t  con£ i rm the  nega t ive  p a r i t y .  Spec t ro scop ic  
f a c t o r s  w i l l  be ob t a ined  by u se  of t h e  exac t - f i n i t e -  
r ange  WBA code WUCK5. 
Ana lys i s  of t h e  d a t a  f o r  6 0 ~ i  and 5 2 ~ r  is now 
beginning.  A ve ry  good energy c a l i b r a t i o n ,  based on 
s t r i p p i n g  t o  w e l l  known l e v e l s  w i th  1 2 c  and 6 0 ~ i  
t a r g e t s ,  ha s  g iven  e x c i t a t i o n  e n e r g i e s  f o r  t h e  8' 
s t a t e s  of 6 0 ~ i  t o  an  accuracy  of + l o  keV, pe rmi t t i ng  a 
v e r y  c l e a r  comparison t o  t he  e l e c t r o n  s c a t t e r i n g  da t a .  
The v a l u e s  i n d i c a t e d  i n  Fig. 2 a r e  from t h e  on- l ine  
peak f i t t i n g  and may change somewhat w i th  more c a r e f u l  
peak f i t t i n g .  
T =3 T = 2  t' ' 
+Permanent Address : Physics  Department, Un ive r s i t y  of 
Birmingham, Birmingham, B15 2TT England 
o j  
o momentum 
1 )  D.F. Geesaman e t  a l . ,  IUCF S c i e n t i f i c  and Technica l  
Report  1983, p.17. 
2) R.A. Lindgren e t  a l . ,  Bul l .  Am. Phys. Soc. 27, 697 
(1982) 
3 )  G.S. Adams e t  al., Phys. Rev. L e t t .  38 1387 (1977); 
S. Yen e t  a l . ,  Phys. L e t t .  105B, 421 (1981); 
C. Olmer e t  a l . ,  Phys. Rev. L e t t .  43, 612 (1979); 
S. Yen et a l . ,  Phys. Rev. C 27, 1939 (1983). 
4 )  G. Ciangaru e t  a l . ,  Phys. Rev. C 2, 2017 (1984). 
5) L. Zamick, Phys. Rev. C 29, 667 (1984). 
6)  R.A. Lindgren e t  a l . ,  Phys. Rev. L e t t .  47, 1266 
(1981) 
7)  B. Zeidman, p r i v a t e  communication. 
8 )  P.D. Kunz, Un ive r s i t y  of  Colorado, unpublished.  


Proton Stripping to Stretched States in 26-Al, 52-Cr, and 60-Si

https://scholarworks.iu.edu/dspace/bitstream/2022/1101/1/iucf_1984_80-81.pdf

Proton Stripping to Stretched States in 26-Al, 52-Cr, and 60-Si

Abstract

Similar works

Full text

Available Versions

IUScholarWorks