HV Cable and Snout Conflict: Problem and Possible Fix James Mott g-2 Tracker Meeting 02/25/16

Change in snout geometry: 22 At test beam, the snout had a big square pocket next to the feedthrough board. In the production design, we’ve moved to a tapered pocket. This caused a conflict between the snout wall and our HV cables

HV Cable: Test Beam Design 33 Side OnTop Down Straws Side Flobber Side Straws Side Flobber Side Flexi Connectors HV Socket HV Header (same on both sides) HV Cable Shrink Tube Epoxy HV connector is a header (pins sticking out) on the feedthru board. Test beam connector was wires soldered on to a socket, then epoxied to give some rigidity.

HV Cable: Conflict with Tapered Snout 44 Side OnTop Down For a comfortable radius of curvature (from trying to bend HV cable and epoxy), the cables run into the bottom and one wall of the snout. Most of the problems come from the HV connector extending a long way into the snout. HV connector HV cable Flexi Feedthru

HV Cable: Conflict in Real Life 55 This really is a problem – I can’t put the feedthrough board in the 3D-model of the snout. The obvious solutions would be to change the design of the feedthrough board or the snout. But feedthroughs are made ($5k) and snout casts are made ($5k) We tried a few different solutions here but kept running into problems with HV clearance. This is the best we think we can do without re-making boards…

Proposed Solution: Comparison 66 OLD NEW Side OnTop Down Cable board with sockets New HV header

New HV Design: Mechanical Prototype 1 77 Used prototyping board to mock-up cable board – dimensions and wire positions are approximate: New lower profile HV header with round pins (old on right) Feedthru Moved one cable over 0.1” so it doesn’t hit wall – should still be OK for HV clearance Sockets for plugging onto header Will have through holes for soldering cables – probably need to epoxy too

New HV Design: Mechanical Prototype 2 88 Side OnFrom inside snout

New HV Design: In Snout 99 With new design it fits comfortably in snout (and better than test beam design did) Cost is only a few hundred dollars for new connectors and adapter boards Any exposed HV will be conformally coated. But we might want to also coat or put kapton inside the snout – clearance was small before and now is a little smaller…

Current HV Clearance vs Test Beam: Vertical 10 Test BeamProduction Within board, clearance is unchanged with minimum of 3.5 mm Closest point to snout vertically was 5 mm - it’s now 4.1 mm Remember we’re expecting HV to be up to ~1.8 kV

Current HV Clearance vs Test Beam: Horizontal 11 Test BeamProduction Closest point to snout horizontally was 3 mm and it’s now 2.7 mm