1. Neutron-induced Reactions
X(n,b)Y
b(Q+En)
n(En)
Probability to penetrate the potential barrier
Po(Ethermal) = 1
P>o(Ethermal) = 0
For thermal neutrons
Q >> En
b(Q)  constant
Non-resonant
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

2. Neutron-induced Reactions
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

3. Nuclear and Radiation Physics, BAU, 1st Semester, 2006-2007 (Saed Dababneh).

4. Neutron-induced Reactions
n-TOF
CERN
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

5. Nuclear and Radiation Physics, BAU, 1st Semester, 2006-2007 (Saed Dababneh).

6. Neutron-induced Reactions
n_TOF
CERN
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

7. Neutron-induced Reactions
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

8. Charged Particle Reactions
What is the Gamow Peak?
Nuclear
Radius
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

9. Charged Particle Reactions
Electron Screening
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

10. Charged Particle Reactions
e2 = 1.44x10-12 keV.m
Tunneling probability:
In numerical units:
For -ray emission:
Sommerfeld parameter
Gamow factor
Multipolarity
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

11. Charged Particle Reactions
Nuclear (or astrophysical) S-factor
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

12. Charged Particle Reactions
EC = ??
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

13. Resonance Reactions E  t
CN  particle emission  E  E > spacing between virtual states  continuum. (Lower part  larger spacing  isolated resonances).
D  bound states  -emission  E  isolated states.
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

14. Resonance Reactions a + X  Y + b Q > 0 b + Y  X + a Q < 0J Ex
a + X  Y + b Q > 0
b + Y  X + a Q < 0
Excited
State
Entrance Channel
a + X
Exit
Channel
b + Y
Inverse Reaction
Compound Nucleus C*
Identical
particles
Nature of force(s).
Time-reversal invariance.
Statistical
Factor () QM
HW 30
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

15. (selected energies with large X-section)
Resonance Reactions
Projectile
Projectile
Target
Target
Q-value
Q-value
Q + ER = Er
E = E + Q - Eex
Direct Capture
(all energies)
Resonant Capture
(selected energies with large X-section)
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

16. Nuclear and Radiation Physics, BAU, 1st Semester, 2006-2007 (Saed Dababneh).

17. Resonance Reactions  HW 31
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

18. Resonance Reactions Damped Oscillator Oscillator strength Damping
factor
eigenfrequency
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

19. Resonance Reactions Breit-Wigner formula All quantities in CM system
Only for isolated resonances.
Reaction
Elastic scattering
Usually a >> b.
HW 32 When does R take its maximum value?
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

20. Resonance Reactions Ja + JX + l = J (-1)l (Ja) (JX) = (J)
Exit
Channel
b + Y
Ja + JX + l = J
(-1)l (Ja) (JX) = (J)
(-1)l = (J) Natural parity. J Ex
Excited
State
Entrance Channel
a + X
Compound Nucleus C*
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

21. radiative capture (a,)
Resonance Reactions
What is the “Resonance Strength” …?
What is its significance?
In what units is it measured?
Charged particle
radiative capture (a,)
(What about neutrons?)
Cross section EC
  a
  
Energy
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

22. Resonance Reactions 14N(p,) HW 33 Huge challenge to experimentalists
Q = ??
EC = ??
ER = 2.0 MeV
Formation via s-wave protons, J = ½, p = 0.1 MeV,
dipole radiation E = 9.3 MeV,  = 1 eV.
Show that  = 0.33 eV.
If same resonance but at ER = 10 keV
p = ?? E = ??  = ??
Show that  = 3.3x10-23 eV.
Huge challenge to experimentalists
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).

23. Resonance J Estimated
-transfer reactions
Angular distribution
Resonance J Estimated
Energy (keV)  (eV)
Experimental upper limit < 1.7 eV
18O(, )22Ne
Nuclear and Radiation Physics, BAU, 1st Semester, (Saed Dababneh).