ENTRY            M0652   20040514
SUBENT        M0652001   20040514                                 
BIB                 13         39                                 
TITLE      Statistical and direct  aspects  of  64Zn  (g,n)  and  
            (g,np)  decay channels in the giant dipole resonance  
            and quasideuteron energy regions.                     
AUTHOR     (T.E.RODRIGUES,J.D.T.ARRUDA-NETO,Z.CARVALHEIRO,J.MESA, 
            A.DEPPMAN,V.P.LIKHACHEV,M.N.MARTINS)                  
REFERENCE  (J,PR/C,68,014618,2003)                                
INSTITUTE  (3BZLUSP)                                              
FACILITY   (LINAC,3BZLUSP) University  of  De Sao Paulo (Brazil)  
            60-MeV LINAC.                                         
INC-SOURCE Electron beam.                                         
METHOD     (ACTIV) Measuring  the beta+ activity of the residual  
            products induced  in  64Zn  by electrodisintegration  
            counting the 511-keV  annihilation  g-rays:  63Zn  -  
            T1/2 =  38.47  min,  62Cu - T1/2 = 9.74 min,  62Zn -  
            T1/2 = 9.186 h, 65Zn - T1/2 = 243.7 d.                
SAMPLE     Two nat-Zn foils (8.87(56) and 7.33(47) mg/cm**2.      
DETECTOR   (HPGE)                                                 
ANALYSIS   Electrodisintegration reaction  cross  sections  were  
            measured and   converted   into  photodosintegration  
            reaction cross   sections   using   virtual   photon  
            formalism.                                            
COMMENT    The investigation of statistical and  direct  aspects  
            related to  the  (g,n)  and (g,np) decay channels of  
            64Zn in  the  giant  dipole  resonance   (GDR)   and  
            quasideuteron (QD) energy regions was performed by a  
            trial function fitting to the respective  (e,n)  and  
            (e,np) electrodisintegration   yields   measured  by  
            residual activity.  Absolute cross section  for  the  
            reaction  64Zn(g,n)  from  threshold  to  60 MeV was  
            obtained for the first time.  Statistical and direct  
            contributions to  the  (g,np)  process,  later being  
            remarkably well  described  by  the  QD  model  were  
            separated in  the  interval 40 - 60 MeV.  A possible  
            direct contribution for the (g,n) decay in  GDR  was  
            also addressed.   The  total  photoabsorption  cross  
            section of 64Zn was reevaluated up to 21 MeV.         
STATUS     (APRVD) Tht data in form of tables were received       
            from the authors (M.N.Martins).                       
HISTORY    (20040428C)                                            
ENDBIB              39                                            
NOCOMMON             0          0                                 
ENDSUBENT           42