Transcript Document

sinv in ABLA
• Particle-decay width in Weisskopf-Ewing approach:
2  s  1
2  m
 Ei , J i  


2
2  π   Ei , J i  π  
Ei  S
 s    E
inv
f
, J f    B dE f
0
 = Ei - S - Ef
• Inverse cross section:
- Strong absorption model – pR2
- Optical model –
2
l


2

l

1

π



T

  
l
- Parameterization (e.g. NASA)
Strong absorption model
• Analogous to the diffraction of light by a totally
absorbing disc or sphere
 B
s inv    π  R  1 
 
2


Rgeom  1.16 fm  A1 3  A2 3 ,
1
1

,

and
R  Rgeom  R
2
R 
2    
B - Bass model for fusion of two spherical nuclei.
Comparison with data
Comparison with data
Comparison with data
Comparison with data
Comparison with SCAT2 optical model
- SCAT2 model - O. Bersillon:
- spherical OM
- real potential: Woods-Saxon, imaginary - volume: WS,
surface: derivative WS or Gaussian
- OM parameters: several options, also as input
Question
- Parameters of different optical models fitted to the
experimental data
- But – experimental data (capture cross section, elastic
scattering …) measured on “cold” nuclei, what we need for sinv
is capture on “hot” nuclei.
- Are such optical models applicable for calculating emission of
particles (especially neutrons) from excited nuclei?