432 8 Nuclear Physics – II
Fig. 8.4Resonance and
potential sacttering and
absorption cross-sections as a
function of neutron energy
whereg=
(2Ic+1)
(2Ia+1)(2Ix+1)
(8.36)
Γaτa=;Γbτb= (8.37)
σel=
π
k^2
∣
∣Ares+Apot
∣
∣^2 (8.38)
withAres=
iΓn
(En−ER)+^12 iΓ
(8.39)
and Apot=exp(2ikR)− 1 (8.40)
Optical model
V=−U−iW (8.41)
U=vk 1 (8.42)
W=
2
vk (8.43)
wherev=
√
2 E/m (8.44)
is the velocity of the incident nucleon.
k=(2mE)^1 /^2 /; (8.45)
k 1 =[2m(E+U)]^1 /^2 / (8.46)
K=
1
λ
=
Aσ
vol
=
3 σ
4 πr 03
(8.47)
Direct reactions(Reactions without compound nucleus formation)
- Inelastic scattering
- Charge exchange reactions
- Nucleon transfer reactions