1. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 1 Electron pick-up. ~1/E What about fission fragments????? Bragg curve stochastic energy straggling. Energy loss is a stochastic process, thus energy straggling. Principles of Spectrometry Target Accelerated beam

2. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 2 Hadrontherapy

3. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 3 Principles of Spectrometry Accelerated beam

4. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 4 Range of charged particles Compare to gamma … !!! Range straggling? Mean and extrapolated range. An “old” idea to measure energy..! Surface barrier, PIPS. For a detector to register the full energy of charged particles, its thickness should be more than the range at that energy. Sometimes we look for partial energy. E-  E detection. position sensitive detectors. Energy and position sensitive detectors. Radioactive ion beams. Radioactive ion beams. Counts number Principles of Spectrometry

5. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 5 E-  E detection. Principles of Spectrometry

6. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 6 Use SRIM Data to reproduce the graphs. Energy deposited in an absorber (or detector). Or, if “thin” absorber: Both are not accurate. Why? You can do it better with SRIM. Principles of Spectrometry

7. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 7 Principles of Spectrometry

8. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 8

9. 9 Stopping time Problem…!! Detector response time. Effect on Doppler shift and broadening in nuclear reactions. Compare the application of scaling laws and Bragg-Kleeman rule with SRIM. Work out many examples. Ranges? Principles of Spectrometry Units? Applicability? HW 12 HW 13

10. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 10 Fast Electron Interactions. Collisional Collisional Radiative (Bremsstrahlung) Radiative (Bremsstrahlung) What is the main difference for positrons? Principles of Spectrometry

11. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 11 Range.. ! Range x density Monoenergetic Electron Beam What about  electrons? Principles of Spectrometry

12. 12 nearly monoenergetic. IC Auger High keV to MeV range. Few keV. Energy Resolution Easily self absorbed. Principles of Spectrometry Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

13. 13 Backscattering Fraction backscattered Detector entrance window or dead layer. Source backing. Principles of Spectrometry

14. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 14 Principles of Spectrometry

15. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 15 Principles of Spectrometry  From 185 W. Endpoint = 0.43 MeV. In Al

16. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 16 Nuclear Reactions X(a,b)Y First in 1919 by Rutherford: 4 He + 14 N  17 O + 1 H 14 N( ,p) 17 O Incident particle may: change direction, lose energy, completely be absorbed by the target…… Target may: transmute, recoil…… b =   Radiative Capture. If B.E. permits  fission (comparable masses). Different exit channels a + X  Y 1 + b 1  Y 2 + b 2  Y 3 + b 3 …….

17. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 17 Nuclear Reactions Recoil nucleus Y could be unstable   or  emission. One should think about:  Reaction dynamics and conservation laws i.e. conditions necessary for the reaction to be energetically possible.  Reaction mechanism and theories which explain the reaction.  Reaction cross section i.e. rate or probability.

18. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 18 Nuclear Reaction Energetics (revisited) If the reaction reaches excited states of Y 58 Ni( ,p) 61 Cu Highest proton energy less proton energy even less ….

19. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). 19 Nuclear Reaction Energetics (revisited)

20. 20 Nuclear Reactions Categorization of Nuclear Reactions According to: bombarding particle, bombarding energy, target, reaction product, reaction mechanism. Bombarding particle:  Charged particle reactions. [ (p,n) (p,  ) ( ,  ) heavy ion reactions ].  Neutron reactions. [ (n,  ) (n,p) ….. ].  Photonuclear reactions. [ ( ,n) ( ,p) … ].  Electron induced reactions…………. Bombarding energy:  Thermal.  Epithermal.  Slow.  Fast.  Low energy charged particles.  High energy charged particles. Neutrons. ? Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

21. 21 Nuclear Reactions Targets:  Light nuclei (A < 40).  Medium weight nuclei (40 < A < 150).  Heavy nuclei (A > 150). Reaction products:  Scattering. Elastic 14 N(p,p) 14 N Inelastic 14 N(p,p / ) 14 N*  Radiative capture.  Fission and fusion.  Spallation.  ….. Reaction mechanism:  Direct reactions.  Compound nucleus reactions. More …. What is a transfer reaction….????? Stripping Pickup Resonant Non-resonant Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).