Slides from Mike Sullivan’sPresentation at the 2E34 Meeting

Side view of BaBarBackward Q1/Q2 bellows

Forward Q1/Q2 bellows

Forward Q2 chamber

Close up of damage to the tiles

RF seal – note the bolt head

RF finger seen in borescope videos

Close up of RF seal

New Q1/Q2 Bellows RF Seal

• 3/6 - New RF Seal Plate submitted to MFD

• 3/3 - Prototype RF Seal made using existing SPEAR3 RF seal die and another existing die.

Picture of bellows before installation in 2002

This picture is a miracle!! The correct bellows section in the correct orientation!!!Thank you Scott!!

Tentative Conclusion

• The design flaw in the RF seal made a weak point in the system – it allowed voltage to develop between the RF seal and the Cu under the tiles

• When the beam currents got high enough some form of an arc damaged this tile – the tile is made of SiC 40% and AlN 60%

• The damaged tile could not hold off as much voltage as before and hence the maximum beam currents were limited

There are many more pictures in the following location:V driveThen AD folderThen PEP-II Upgrade folderThen photoGallery folderThen Q1Q2 RF seal damaged folder