Target meeting: 24Feb10, 09:00

Present: PH, CB, JT, EC, PS, JL, GB, KL

1. Review of actions:

• PS, JL: write specification for generation of MICE target signal for ISIS BPS.
  Stands.  PS at RAL next week so will try and make progress.
   
• PS: To guide readout and analysis of thermocouple in target housing.
  Done.  Need to check analysis.
   
• AD/PH: Will find a way of automating processing so that BLOC can check the histogram.
  Stands.
   
• PH: Inform trgt group how archiving of target data to GRID will be done.
  Stands.
   
• PS: Look at ways of including the "legal spill" marker feature.
  Stands.  PS will try and progress this next week too.

2. Progress on mechanical design and fabrication:

2.1 Target assembly [2] and [3]: JT

• Shaft was still felt to be running smoothly before disassembly started, but had more 'slop'.  Consistent with wear.
• Target disassembled.  Significant amounts of deposit found on top bearing.  Both flats managed by plastic.  Noted that flat was only polished on one side.  Rough side had significantly more deposit.  New shafts will be polished on both surfaces.  Should reduce dust production.
• Also found some dust inside vacuum tube.  Much smaller amount of dust on bottom bearing.
• Some dust found on shaft below the bearing. 
• Inspection of bellows carried out, little evidence of dust inside the bellows.  Some dust was adhering to the shaft.
• Clear evidence of wear.  Possible that all (or a substantial proportion) of the dust could have come from the rough surface on the unpolished flat.
• Next step is to inspect surfaces with microscope.
• More shafts being manufactured.  Should alleviate wear.
• Some other plastics under consideration have better thermal expansion properties.
• Position of stop on new shaft under consideration: issue is distortion of shaft.  Possibility of putting stop below the bearing under consideration.  Alternative design for stop might include a 'dust-catcher' feature.  To be discussed at the w/s.
• Actions:
  • KL, JT: Invite DF, AS, EMcC to R78 for inspection of target
  • JT: Make project plan for making new pair of targets in time for next target w/s.  Plan should include a 'crash programme' to be implemented if the target in ISIS fails.

2.2 Performance analysis of T2#2: PH

• See slides: here
• Target did not fail since performance was within the fluctuations of the beam.  So, if the dust is acceptable the lifetime can be defined and the target used in the machine.
• Target shows signs of running in, stable operation, then some signs of wear.  Believe could define 'lifetime' from this history (e.g. could run up to 1.3M pulses, say).

2.3 Stator: CB, GB, OT

• CB:
  • New stator manufactured and tested.  Can be transported to RAL and welded. 
• GB:
  • JPG circulated (here).  Worry about precision of measurement because of position of probe in bore.
  • Expect to have the system in place by the end of net week.  Hope for initial measurements in time for the target w/s.
• OT:
  • No report this week.

3. Target electronics and DAQ: PS, JL

• PS:
  • Some progress on firmware.  Now close to the point where work needs to be done at RAL.
  • Have arranged with JL to work together at RAL.
• JL:
  • No report this week.

4. Target paper: CB

• No report this week.

5. Next meeting

• Date of next phone call: 03Mar10; 09:00
• Date of w/s: Friday: 12Mar10, 11:00 start; Imperial
• MICE/ISIS target w/s: afternoon of 18Mar10

6. AoB

• JT: Offers GB for pieces of CF tube.

7. Summary of actions