MeVArc 2010 Workshop

6 May 2010, 08:00 → 7 May 2010, 18:30 Europe/Zurich

40/S2-D01 - Salle Dirac (CERN)

Sergio Calatroni (CERN), Flyura Djurabekova (University of Helsinki), Kai Nordlund (University of Helsinki), Walter WUENSCH (CERN)

Vacuum breakdowns caused by high voltages and high-power rf are extremely complex phenomena, however significant advances understanding and quantitative modeling are being made. The latest developments in theory, simulation, supporting experimental investigations and application to high-gradient device design will be covered in this workshop. The workshop seeks to bring together the diverse communities such as accelerators, plasma fusion and satellite communication which must contend with vacuum breakdown. This workshop will be preceded by a meeting on the development of high-power X-band rf structures (X-Band Structure) for CLIC.

Thursday 6 May ¶

Introduction and general physics¶

1 Welcome address¶

Speaker: Jean-Pierre Delahaye (CERN)

2 Introduction to CLIC and breakdown in rf structures¶

Speaker: Walter WUENSCH (CERN)

Slides breakdown_in_rf_ww.pdf breakdown_in_rf_ww.pptx

3 Discussion¶

4 BD problem in satellites¶

Speaker: David Raboso

5 Discussion¶

6 Arc surface damage in fusion reactors¶

Speaker: Volker Rohde

Slides rohde_cern1005.pdf

7 Discussion¶

10:40 Coffee Break and posters

8 Physics of arc plasma devices¶

Speaker: Andre Anders

Slides Anders_cathodicArcs2010-05-04.pdf

9 Discussion¶

10 Challenges simulating low temperature collisional plasmas¶

Speaker: Matthew Hopkins (Sandia National Laboratories)

Slides

• 4-way-solution-2D-shaped-2008-06-22.avi
• Ar+-3D-shaped.avi
• Hopkins_CERN_2010_presentation_2010-04-25.ppt
• proc-ids-3D-shaped-2008-06-23.avi
• proc_ids.avi

11 Discussion¶

12 Distinguishing between work function and geometric field enhancement effects in field emission¶

Speaker: Dr Wei Gai (Argonne National Laboratory)

Slides BA2007-schottky.pdf BA2007-schottky.ppt

13 Discussion¶

12:40 Lunch

Experiments and diagnostics¶

14 DC breakdown measurements¶

Speaker: Mr Sergio Calatroni (CERN)

Slides DCSpark-BreakdownWorkshop.pdf DCSpark-BreakdownWorkshop.pptx

15 Discussion¶

16 The Electric Dipole Moment of the proton in an all electric storage ring¶

Speaker: Dr Yannis Semertzidis (BNL)

Slides YkS_CERN_20100506.pdf YkS_CERN_20100506.ppt

17 Discussion¶

18 Breakdown experiments simulations in waveguides¶

Speaker: Dr Valery Dolgashev (SLAC)

Slides

• Breakdown_PIC_simulations_CERN_1402_4May2010.pdf
• Breakdown_PIC_simulations_CERN_1402_4May2010.pptx
• movies.zip

19 Discussion¶

20 High gradient electrodes for pulsed electron gun¶

Speaker: Martin Paraliev (PSI)

Slides Experimental Study of DLC Coated Electrodes for Pulsed Electron Gun

21 Discussion¶

16:00 Coffee break and posters

22 Spectroscopy of breakdowns¶

Speaker: Jan Kovermann (III. Physikalisches Institut (B) - Rheinisch-Westfaelische Tech.)

Slides BDWS2010.pdf BDWS2010.pptx

23 Discussion¶

24 Breakdown-related Surface Evaluation by Scanning Field Emission Microscope¶

Speaker: Yasuo Higashi (KEK)

Slides Breakdown_physics_workshop100505Higashi.pdf Breakdown_physics_workshop100505Higashi.ppt

25 Discussion¶

26 In-situ breakdowns in SEM¶

Speaker: Roger Ruber (University of Uppsala)

Slides vz-sem-20100506.pdf vz-sem-20100506.ppt

27 Discussion¶

Friday 7 May ¶

Theory and simulation¶

28 Multiscale model¶

Speaker: Flyura Djurabekova (University of Helsinki)

Slides BD_WSh_djurabekova.pdf BD_WSh_djurabekova.pptx

29 Discussion¶

30 PIC plasma and MD simulations¶

Speaker: Helga Timko (Univ. of Helsinki, Fac. of Science-Unknown-Unknown)

Slides BRD10_timko.pdf BRD10_timko.ppt

31 Discussion¶

32 Dark current calculations in RF structures¶

Speaker: Arno Candel (SLAC National Accelerator Laboratory)

Slides Breakdown10_Candel.pdf Breakdown10_Candel.pptx

33 Discussion¶

10:30 Coffee break and posters

34 Arc simulations using Aleph, a PIC/DSMC code¶

Speaker: Paul Crozier

Slides

• arc_simulations_using_Aleph.pdf
• arc_simulations_using_Aleph.ppt
• density_37.wmv
• potential_37.wmv

35 Discussion¶

36 Arc modeling at Sumy, Ukraine¶

Speaker: Dr Serhiy Mordyk (of Applied Physics National Academy of Sciences of the Ukraine)

Slides iap_nasu2010.pdf iap_nasu2010.ppt

37 Discussion¶

38 New results from arc modeling and our workshop on Unipolar Arcs¶

Speaker: Mr Jim Norem (Argonne National Lab)

Slides CERN_May_7_norem.pdf

39 Discussion¶

12:30 Lunch

Pulsed surface heating experiments & Theory¶

40 Pulsed surface heating and BDR¶

Speaker: Chris Adolphsen (SLAC)

Slides Adolphsen_Pulse_Heating.pdf Adolphsen_Pulse_Heating.ppt

41 Discussion¶

42 Introduction to dislocations dynamics¶

Speaker: Steve Fitzgerald

Slides Apologies for lack of animations

43 Discussion¶

15:00 Coffee break and posters

44 Asperities on the surface due to dislocations activity¶

Speaker: Aarne Pohjonen (University of Helsinki)

Slides Pohjonen_CLIC070510-15.pdf

45 Discussion¶

46 Metallurgy of pulsed surface heating¶

Speaker: Markus Aicheler (Ruhr-Universitaet Bochum)

Slides MAicheler_BDWS_2010_05_07.pdf MAicheler_BDWS_2010_05_07.pptx

47 Discussion¶

48 Experimental Evaluation of Magnetic Field Effects on Breakdown Rates¶

Speaker: Prof. Sami Tantawi (SLAC)

Slides Mag1.pdf Mag1.pptx

49 Discussion¶

50 New features observed with SEM in-lens detector in the vicinity of breakdown craters¶

Speaker: Gonzalo Arnau Izquierdo (CERN)

Slides New_features_observed_with__SEM_in-lens_detector_in.pdf New_features_observed_with__SEM_in-lens_detector_in.ppt

51 Disscussion¶

52 Announcementof workshop 2011¶

Speaker: Kai Nordlund (University of Helsinki)

Slides breakdown11_welcome.pdf breakdown11_welcome.pptx