1 / 13

Coulomb Scattering

Coulomb Scattering. Elastic or inelastic. Elastic  Rutherford scattering. At any distance:. V = 0 T a = ½mv o 2 l = mv o b. v min. v o. r min. b. d. No dependence on . Coulomb Scattering. Closest approach “d”. E  = E Coulomb  d = 2kZe 2 /E 

ona
Download Presentation

Coulomb Scattering

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Coulomb Scattering • Elastic or inelastic. • Elastic  Rutherford scattering. • At any distance: V = 0 Ta = ½mvo2 l = mvob vmin vo rmin b d Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh). No dependence on 

  2. Coulomb Scattering • Closest approach “d”. • E = ECoulomb d = 2kZe2/E • What about the recoil nucleus? • HW 9Show that • where mN : mass of the nucleus • m : mass of alpha • What are the values of d for 10, 20, 30 and 40 MeV  on Au? • How does this explain … ? Nuclear and Radiation Physics, BAU, Second Semester, 2009-2010 (Saed Dababneh).

  3. Coulomb Scattering Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

  4. Coulomb Scattering b < b >  dbd n target nuclei / cm3 x target thickness (thin). nx  target nuclei / cm2 HW 10 Show that and hence b Rutherford cross section Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

  5. Coulomb Scattering Study Fig. 11.10 (a,b,c,d) in Krane See also Fig. 11.11 in Krane. HW 11 Show that the fraction of incident alpha particles scattered at backward angles from a 2 m gold foil is 7.48x10-5. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

  6. Coulomb Scattering • RBS – Channeling. • Ion implantation. • Occupational or substitutional impurities. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

  7. Coulomb Scattering • Elastic  Rutherford scattering. • Inelastic Coulomb excitation. See the corresponding alpha spectrum of Fig. 11.12 in Krane. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

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

  9. Principles of Spectrometry • Interaction of heavy charged particles • Electronic or nuclear (Rutherford, nuclear reactions, …) • or radiative (Bremsstrahlung). ? Al in Al Excitation Ionization ion-pair, suppress recombination in detectors. Energy loss SRIM http://www.srim.org • Depletion layer. • Delta rays and secondary electrons. • Electron suppression for charge integration in accelerators. • Faraday Cup. • Tracks. Detectors mainly designed to make use of electronic interactions. Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

  10. Principles of Spectrometry Stopping power Bethe-Bloch formula ~1/E ~1/E Minimum ionizing particles (mip). Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

  11. Principles of Spectrometry Units (conversion) You will encounter this when you run SRIM eV / Å keV / m MeV / mm keV / (g/cm2) MeV / (mg/cm2) keV / (mg/cm2) eV / (1x1015 atoms/cm2) Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

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

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

More Related