1. Triple junction 'shed' optimization for the 200kv CEBAF gun upgrade
Carlos Hernández
Gabriel Palacios
3/8/2017

2. Outline Ball vs T cathode Top flange accurate modeling
Shed optimizations
Triple junction
Cusp

3. Ball vs T-cathode -250 kV side view

4. Sphere vs T-cathode -250 kV front view

5. Top flange

6. Top flange potentials along rubber-insulator boundary.

7. Sheds

8. Sheds

9. Sheds

10. Sheds

11. Sheds

12. Original vs best (mod 2.3)

13. Original vs best (mod 2.3) potential

14. Original vs best (mod 2.3) E field along x-axis

15. Original vs best (mod 2.3) E field along y-axis

16. Cathode-anode

17. Original vs best (mod 2.3) Ex field on cathode-anode gap

18. Original vs best (mod 2.3) Ey field on cathode-anode gap

19. Original vs best (mod 2.3) Ey field on cathode-anode gap

20. Original vs best (mod 2.3) Ey field on cathode-anode gap

21. Original vs best (mod 2.3) cathode-anode gap

22. Conclusions
The simulation quality improved by using detailed geometry.
The shed
should be close near the triple point and then curve away softly to optimize the fields around that area.
does not have a strong effect on the potential and electric fields along the rubber-insulator boundary.
slightly modifies the y component of the electric field in the cathode-anode gap.