1. LHC e - cloud simulations C.Octavio Domínguez, Giovanni Rumolo, Frank Zimmermann 17 th January2011 - e - cloud simulations

2. 2 Contents 1)LHC IR3: I.State of the art 2) LHC arc dipoles: I.Emittance scan (onset, build up & energy distribution) II.Intensity scan (build up & x-flux distribution) 17 th January2011 - e - cloud simulations

3. 3 Contents 1)LHC IR3: I.State of the art 2) LHC arc dipoles: I.Emittance scan (onset, build up & energy distribution) II.Intensity scan (build up & x-flux distribution) 17 th January2011 - e - cloud simulations

4. 4 LHC IR3 First idea  Try to reproduce this plot, BUT  4 parameters: P, SEY,  max and R

5. 5 17 th January2011 - e - cloud simulations LHC IR3 – 8.85  s ~ Factor 6 ~ Factor 3 Memory effect

6. 6 17 th January2011 - e - cloud simulations LHC IR3 – 8.85  s ~ Factor 1.1 No memory effect ??

7. 7 17 th January2011 - e - cloud simulations LHC IR3

8. 8 17 th January2011 - e - cloud simulations LHC IR3 – Energy distribution

9. 9 17 th January2011 - e - cloud simulations LHC IR3 – Energy distribution

10. 10 17 th January2011 - e - cloud simulations LHC IR3 – Work to do  Look at 28.85 and 38.85  s  Look at the flux (maybe related to the pressure rise)  Make the study for individual batches of 12, 24 and 36 bunches  …

11. 11 Contents 1)LHC IR3: I.State of the art 2) LHC arc dipoles: I.Emittance scan (onset, build up & energy distribution) II.Intensity scan (build up & x-flux distribution) 17 th January2011 - e - cloud simulations

12. 12 LHC arc dipoles -  scan 17 th January2011 - e - cloud simulations Geometry: Parameters: N b = 1.1 · 10 11 ppb; B = 0.535 T (dipolar field) ; s z = 0.118 m e max = 230 eV ; R = 0.7; P=1nTorr Filling scheme: 1 batch (36 bunches) 22 mm 18 mm

13. 13 17 th January2011 - e - cloud simulations LHC arc dipoles -  scan e N (  m) SEY (onset/significative density) 1 1.9 / 2.3 (~0.5 10 11 ) - 2.4 (~3 10 11 ) 2 1.9 / 2.3 (~0.45 10 11 ) - 2.4 (~3 10 11 ) 3 1.9 / 2.4 (~ 10 11 ) 4 2.0 / 2.4 (~ 10 11 ) 10 2.0 / 2.4 (~ 10 11 )

14. 14 17 th January2011 - e - cloud simulations LHC arc dipoles -  scan Build up

15. 15 17 th January2011 - e - cloud simulations LHC arc dipoles -  scan Build up

16. 16 17 th January2011 - e - cloud simulations LHC arc dipoles -  scan Build up

17. 17 17 th January2011 - e - cloud simulations LHC arc dipoles -  scan Energy distribution

18. 18 17 th January2011 - e - cloud simulations LHC arc dipoles -  scan Energy distribution

19. 19 17 th January2011 - e - cloud simulations LHC arc dipoles -  scan Energy distribution

20. 20 17 th January2011 - e - cloud simulations LHC arc dipoles -  scan Energy distribution

21. 21 Contents 1)LHC IR3: I.State of the art 2) LHC arc dipoles: I.Emittance scan (onset, build up & energy distribution) II.Intensity scan (build up & x-flux distribution) 17 th January2011 - e - cloud simulations

22. 22 LHC arc dipoles - N b scan 17 th January2011 - e - cloud simulations Geometry: Parameters:  N = 2.3  m; B = 0.535 T (dipolar field) ; s z = 0.118 m e max = 230 eV ; R = 0.7; P=1nTorr SEY=2.5 (above multipacting onset) Filling scheme: 1 batch (36 bunches) 22 mm 18 mm

23. 23 17 th January2011 - e - cloud simulations LHC arc dipoles - N b scan Build up

24. 24 17 th January2011 - e - cloud simulations LHC arc dipoles - N b scan Build up

25. 25 17 th January2011 - e - cloud simulations LHC arc dipoles - N b scan x flux distribution

26. 26 17 th January2011 - e - cloud simulations LHC arc dipoles - N b scan x flux distribution

27. 27 17 th January2011 - e - cloud simulations LHC arc dipoles - N b scan x flux distribution

28. 28 17 th January2011 - e - cloud simulations

29. 29 17 th January2011 - e - cloud simulations