Plan for MRPC Production Yongjie Sun Center of Particle Science and Technology University of Science and Technology of China

Plan for MRPC Production

Yongjie Sun

Center of Particle Science and TechnologyUniversity of Science and Technology of China

Mar. 31, 2011 STAR MTD workshop, USTC 2

Outline

Material Module assembly

procedure Performance test Time schedule Summary and outlook

QC. & QA.

QC. & QA. QC. & QA.


1. Material list

Use the same material at different sites is preferred. Otherwise, the equivalent must be proved.

Material length width thickness Notes

Inner glass 874 ±0.2 543±0.2 0.7±0.02 5 pieces

Outer glass 890±0.2 559±0.2 1.1±0.02 2 pieces

Graphite liquid electrode 882 551 ~ 4 MΩ/□

Mylar 895 564 0.15±0.01 2 pieces

PCB 915±0.2 580±0.2 0.9 ±0.05 2 pieces, 12 strips, 0.035 thick.

honeycomb 890±1 559±1 10±0.3 2 pieces

Double-side tape 890 559 0.13 2 pieces, for the honeycomb

Fishing line 0.25±0.005 6 gaps

Support block 30±0.2 18±0.2 7.5±0.05 8 pieces

HV wire By USA

signal cable By USA

Unit: mm


Quality control on the material

Glass Measure the dimensions (spot check of 20%) Check the surface quality

Pcb Dimensions, the scratch on the strips

Honeycomb Dimensions, surface quality

Mylar foil: thickness Fishing line

Dimension check of each coil Support block: thickness

Material with faults will be returned back to factory.


2. Assembly procedure

Material cleaning Glass washing: by hot steam and alcohol Honeycomb, mylar, pcb, support block…

Electrode painting Protect the edge of glass with tape (4 mm) Applying the graphite painting Drying for 24 hours Measure the surface resistivity

Preparations


Assembly procedure

adhere the honeycomb to pcb with double-side tape.

put the screws into the bottom pcb for supporting fishing line.


Assembly procedure

Put the mylar on the surface of pcb. Put the outer glass (with electrode p

ainting facing outside) on the mylar.

The HV connection was made by adhesive graphite tape at two corners where Mylar has been cut out.


Assembly procedure

Run the fishing line between the screws and put the inner glass on top of it.

……


Assembly procedure

Put the top pcb (with honeycomb, mylar and another outer glass) on.

Put iron bricks on top of the structure and press for more than 12 hours.

Fix the structure with pins along the edges. Install the support blocks between the pcbs. Solder the HV wire and signal “pigtail” cabl

e. Protect the HV solder point with CAF4 silicon.


QA. & QC. during assembly

Check the cleanness of material during the assembly. Blow off the dust with pure N2 if needed.

Measure the thickness between pcbs at 16 points along the edges. The uniformity should be less than 0.3 mm.

Check the connection of HV and signal cable.


3. Performance test

Install the module into the gas box and flow the working gas for more than 48 hours.

Training with HV for 48 hours. Test the leak current and noise rate. Take the cosmic ray data at 2 different

positions for efficiency and time resolution test (24h for each position).

Need all the modules take the cosmic ray test?

20%: efficiency and time resolution Others: leak current and noise rate


Performance standard

Noise rate: <400 Hz/strip Leak current: < 40 nA Efficiency: > 90% Time resolution: < 120 ps (for 90% chan

nels)


Documents for QA. & QC.

Recording Tables for QA check and test results

Manufacture card QA check Cards

A web-based database will be available similar to that of STAR TOF.


4. Time schedule

2011.4 – 2011.6 finalizing the design

2011.6 – 2011.11 20% 2011.11 – 2012.5 40% 2012.5 – 2012.11 40%


QA. & QC. will be strictly performed during the construction.

Hope continue the success of STAR TOF.

Trouble: lack of FEE board.

5. Summary

Thank You ！
