1 / 19

Understanding Neutron Sources through Spallation Physics at WNR Facility

Delve into the origins of neutrons from spallation physics at the WNR Facility, studying moderators, thermalization, diffusion, and scattering processes. Explore the intricacies of nuclear evaporation models, Fermi gases, and moderator functions.

nerys
Télécharger la présentation

Understanding Neutron Sources through Spallation Physics at WNR Facility

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. ? ? ? ? ? Where are the neutrons coming from? Spallation Physics 101

  2. Linear Accelerator Cockroft-Walton Injector WNR Facility Proton Storage Ring

  3. Central Control Room ER1/2 Lujan Center 1L Target

  4. 1L-Target Proton beam Bulk Shield Window Moderators W-targets Reflector

  5. Proton beam Window Moderators W-targets Reflector

  6. Lower Tier Moderators LQD SPEAR Asterix FP8/LAPTRON Pharos FDS NPDF SMARTS SCD FP5 HIPD HIPPO

  7. Upper Tier Moderators NPD-g IN500 DANSCE PCS

  8. p+ Spallation Process

  9. Intra-Nuclear Cascade

  10. Statistical Thermodynamics Nuclear Evaporation Model Fermi gas of free particles in a collective potential

  11. cold neutrons epi-thermal neutrons thermal neutrons Moderator functions Moderation and Slowing Down Thermalization and Diffusion

  12. Moderation/Slowing Down (incoherent inelastic scattering) #01 Neutron wavelength shorter than lattice parameters Moderator Atoms Epi-thermal neutron

  13. Moderation/Slowing Down (incoherent inelastic scattering) #02

  14. Neutron wavelength of the same order as the lattice constants Coherent elastic scattering (Bragg-reflection) • Scattering on vibrational modes of polyatomic molecules Discrete oscillators Thermalization and Diffusion • Absorption

  15. Maxwell Distribution: Thermal Spectrum

  16. Diffusion equation: Simplified form: Storage Time #01

  17. HIPPO instrument 1L Target Thermal neutrons Sample Location

  18. Do you know where the neutrons are coming from? If not, please fill free to ask questions!

More Related