1. Pyheadtail Comparison and Development
Aaron Axford
Technical Student CERN, Geneva
Nottingham Trent University
Thanks to:
Giovanni Iadarola,
Giovanni Rumolo,
Kevin Li
Michael Schenk

2. Contents Pyheadtail Overview Simulation Parameters
Current Pyheadtail results compared with Headtail
Comparison of Varying number of kicks
Comparison of Varying Dt_ref
Comparison of changing magnetic field
Analysis of repeat simulations

3. Differences for Pyheadtail from Headtail
Presence of the chamber (Shape of the initial ecloud and an electromagnetic boundary)
Losses need to be implemented in order to avoid unphysical motion of large amplitude electrons
Magnetic field
For PyHDTL, B = 0.1T
For HDTL, H motion is frozen

4. Current Pyheadtail results compared to Headtail
Aims
Show that the Pyheadtail model results are comparable to Headtail

5. Simulation Parameters Q26 Optics
Value
Intensity
1.5e11 ppb
Chamber Dimensions (MBB)
Chamber Dimensions (Drift)
X_aper = 6.5e-2m
Y_aper = 2.4e-2m
X_aper = 2.8e-2m
Y_aper = 2.8e-2m
B_multip
1.2133e-1 Tesla
Ring Circumference
6911m
Synchrotron tune
0.059
Betatron tune (Horizontal)
26.13
Betatron tune (Vertical)
26.18
Rf voltage
2e6 V
Dh_sc
0.2e-3

6. Simulation Parameters Q20 Optics
Value
Intensity
1.5e11 ppb
Chamber Dimensions (MBB)
Chamber Dimensions (Drift)
X_aper = 6.5e-2m
Y_aper = 2.4e-2m
X_aper = 2.8e-2m
Y_aper = 2.8e-2m
B_multip
1.2133e-1 Tesla
Ring Circumference
6911m
Synchrotron tune
0.017
Betatron tune (Horizontal)
20.13
Betatron tune (Vertical)
20.18
Rf voltage
5.75e6 V
Dh_sc
0.2e-3

7. Pyheadtail (Top) vs Headtail (Bottom)
Instability threshold
PyHDTL ≈ 4.2e11
HDTL ≈ 3.6e11

8. Pyheadtail (Top) vs Headtail (Bottom)

9. Pyheadtail (Top) vs Headtail (Bottom)
Instability threshold
PyHDTL ≈ 3.1e11
HDTL ≈ 3.2e11

10. Pyheadtail (Top) vs Headtail (Bottom)

11. Comparison of varying Number of kicks
Aims
Look for the effect of the number of kicks simulated on the vertical motion and emittance
Check for any benefit using prime numbers

12. Comparison of varying Number of kicks

13. Comparison of varying Number of kicks

14. Comparison of varying Dt_ref

15. Comparison of varying Dt_ref

16. Comparison of varying Dt_ref

17. Comparison of varying Dt_ref

18. Comparison of varying Dt_ref

19. Number of kicks against Computation Time

20. Comparison of varying Bo
Aims
Observe the outcome when using a Magnetic field varying from 0.1Tesla to 1.9 Tesla

21. Comparison of varying magnetic field

22. Comparison of Repeated reading
Aims
Observe the difference with identical simulations repeated

23. Comparison of Repeated reading

24. Comparison of Repeated reading
Strongly affected by the random number generator

25. Summary
PyHDTL shows a strong reliability with comparison to HDTL results for all tested optics and setups
More investigation needed for varying of repeated simulations