1 / 26

Space Charge Simulations in GPT

Space Charge Simulations in GPT. Simon Jolly Imperial College FETS Meeting, 20/7/05. GPT Space Charge Models. Spacecharge3D - direct relativistic particle-particle interactions. Spacecharge3Dclassic - as above but ignores relativistic effects.

ctharpe
Download Presentation

Space Charge Simulations in GPT

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. Space Charge Simulations in GPT Simon Jolly Imperial College FETS Meeting, 20/7/05

  2. GPT Space Charge Models • Spacecharge3D - direct relativistic particle-particle interactions. • Spacecharge3Dclassic - as above but ignores relativistic effects. • Spacecharge3Dmesh - mesh-based relativistic particle interactions using non-equidistant 3D multi-grid Poisson solver. • Spacecharge2Dline - models each particle as a line charge and calculates 2D field. • Spacecharge2Dcircle - models each particle as 2D charged circle.

  3. GPT beam model • 600mm drift length used with no magnetic elements. • Cylindrical beam model: • x/y = 3.3x10-2 mm-mrad (normalised). • x/y = 10mm; x’/y’ = 10mrad (max). • 60 keV, 70 mA (but 10% space charge). • Pulse length from 1 ns - 1 s (infinite for SC2Dline model). • 10,000 particles (1,000 for quick sim.).

  4. ENVEL/LINTRA Models (JP) • Same beam characteristics, similar model to SC2Dline. • Beam cylindrically symmetric, uniform distribution. • After 600mm drift, sims give similar results: • ENVEL: x = y = 20.47 mm, x’ = y’ = 23.28 mrad. • LINTRA: x = y= 20.55mm, x’ = y’ = 23.41 mrad. • Difference: 0.7% spatial and 1.4% angular. • Compare to GPT results…

  5. LINTRA Results (JP)

  6. GPT results (1ns SC3Dmesh)

  7. 1ns SC3Dmesh emittance

  8. 2ns SC3Dmesh emittance

  9. 5ns SC3Dmesh emittance

  10. 10ns SC3Dmesh emittance

  11. 20ns SC3Dmesh emittance

  12. 50ns SC3Dmesh emittance

  13. 100ns SC3Dmesh emittance

  14. 200ns SC3Dmesh emittance

  15. 100ns SC3Dmesh emittance

  16. 100ns SC3D emittance

  17. 70mA SC2Dline emittance

  18. 70mA SC2Dline emittance (2)

  19. 1ns SC3Dmesh trajectories

  20. 10ns SC3Dmesh trajectories

  21. 100ns SC3Dmesh trajectories

  22. 100ns SC3D trajectories

  23. 70mA SC2Dline trajectories

  24. 70mA SC2Dline trajectories 2

  25. SC2Dline - v - LINTRA Need to use SDDS and Matlab to do proper x’ and emittance calculations…

  26. SC Models Pros and Cons • SC3D: “exact” solution, but very slow (scales as N2) and needs real beam model. • SC3Dmesh: fast version of SC3D, good for quick models with lots of particles (scales as N), but emittance is pulse-length dependent. • SC2Dline: much better emittance measurements due to “flattened” beam, but as slow as SC3D.

More Related