Straw bi-weekly meeting

Tuesday 19 Aug 2025, 09:00 → 10:00 Europe/Zurich

Hans Danielsson (CERN)

To be followed up:

• which straws to use for the long 128-straw prototype
• rename "intermediate prototype" to "long 4-straw prototype" (Peter)
• need to keep track of parts during wiring
• pull-test results
• order frame for the long 4-straw prototype
• check that all holes for screws are present (fixation, support, tooling, ...) on the flanges of the long 128-straw prototype
• QC report from Stefano
• tooling
• vacuum tube recovery
• plan and test how to replace a straw in the long prototype
• find solution for HV connection of Lamina straws

 

Proposal: 

Given the number of HV connectivity parts we have at the moment, it has been proposed to equip: 

0.5m prototype: only 2 straws, one side active, one side passive (2x HV plug active, 2x HV cap, 2x HV plug passive, 2x spring pin, 2 IMC crimp tube, 2x overmolded crimp tube)

long 4-straw prototype: 2 Sefar straws, 2 Lamina straws, both sides active (8x HV plug active, 8x HV cap, 8x spring pin, 8x IMC crimp tube)

Keep 2x HV plug active, 2x HV cap, 2x spring pin as spares, or equip one short straw.

09:00 → 10:00 Updates

Update-August19.pdf

Update-August19.pptx

0.5m prototype:

Zuzana:

• HV connectivity pieces should be fully ready next week
• see presentation for details

 

Johan:

• the study PCB (current) should be ready in a week
• new HV board could be ready in 2-3 weeks

Long 4-straw prototype:

Hans:

• in contact with Remus to prepare parts

 

Michal:

• we should receive plugs for pressurization of Lamina straws this week
• 2 Sefar straws can be used

 

Francois:

• we cannot reuse the old frame pieces, we have to order new ones

Long 124-straw prototype:

Zuzana:

• contacting companies to manufacture ultem and brass pieces - complicated due to holidays
• Minitubes crimp tubes delivery delayed due to holidays, inquiry about new date ongoing

 

Hans:

• in contact with the CERN main workshop to optimize the manufacturing of the supporting tube - more info next week
• estimate delivery date - January 2026 -> possibly go to a company
• tests of spacers

 

Vincent:

• will make modifications of the gas manifold to gain more space for the lateral straws, HV cable, gas connector, material, thickness, ...
• can prepare drawings for mechanical support of the support tube

 

Peter:

• flanges and tube need to be grounded
• they need to be electrically connected together to provide a "shield"
• want to use a source to test straws

General:

Hans:

• EDMS folder for the Straw detector upgrade: EDMS link
• will send an email to Temur asking about straws

 

Michal:

• need to send a QC report to Sefar
• asked about settings for welding - seems to be unstable

 

Peter: 

• at first we need also termination, only after that it might turn out that we don't need it
• Lamina straws: it is not clear if both sides (inner and outer) need to be connected together
• Lamina straws - use metallic straw plug (or none at all), conductive glue to connect the outer layer to the frame and then connect the inside as in welded straws