Meeting 2015-2-11


Potential for last weekend in April run.

Mock data challenge 2 now moved to first week of March

Ed and I will create a loose schedule based on the items below to be discussed at next meeting in two weeks.



The current system is not well ground as the plates that the magnets sit on are floating and not properly bonded to the ground.
The racks are not properly bonded to the plates as they require a copper cable TAPPED into the leg of the rack to the ground.

Daresbury will take care of both of the above as and when they can around rack room setup.


  • The racks are not properly ground to the crates.
  • As they are closely electrically connected and use lemo cables (so 0Volts/ground) each crate should be individually bonded to the grounding strip that runs up the rack.
    *This can be done by tapping a copper cable into the crates themselves and to the rack grounding strip. * This must be done by us and Daresbury will consult (a few weeks) but all in all it shouldn't be too time consuming.

NB, it has been pointed out that at the time of the mock data challenge the rack earth cables were coiled up under the racks were not connected. This may or may not have been an issue but it is worth baring in mind.

DAQ and commissioning (Led by Ed, Craig, David and Paul)

See Eds talk from CM41
1) Clarify and fix noise issues [? days] - * We can run one cryostat for regular runs at different times with different substystems running and various amounts of work i the hall to see if the situation can be replicated and understood.

2) Implement timing derived from the single station test [1 day]
Use the timing we used in 2012 as a starting point for finding the ISIS beam, then re-time in LED systems to this timing..
3) Perform Bias Calibrations [4 day] David has written the calibration software, but this is the first time it is to be used properly.
4) Test New trigger [3 day]
FPGA Trigger now has an implementation of the necessary tracker veto (alive window), but with 10ns of jitter (on a 120ns gate, this is substantial). Needs testing and understanding.
5) External LED pulser test [3 day]
With the correctly biased VLPC's the external LED pulsers must be fired to verify the calibration and obtain gains for each channel.
6) Wave guide attachment [4 days] (possibly) testing with internal LED [1 day]

Once the system is wave guided and calibrated, we can then start looking for the beam.

7) Synchronise alive window to the trigger arrival. [2hrs beam + on-mon] Maximise accepted-triggers to trigger requests.
8) Verify timing of readout trigger and closing of integration gate. [2hrs] In the hall, with a scope.
9) Synchronously move the readout trigger and integration gate. [4hrs beam + on-rec] Looking for space points in the tracker, aiming to maximise: Spacepoints in tracker / Spacepoint in TOF1 AND TOF2

10) Verification of space point finding efficiency against: [1 week beam]
  • Time in spill
  • TOF1-2 time
  • Each station
11) Verification of particle-optical-readout path: [5 days LED + 2 day beam]
  • Use the internal LED system to illuminate internal fibres and measure mean light yield.
    Need to understand/parametrise internal light distribution.
  • Combine with beam data to obtain a full understanding.
  • Use to generate a large statistics measurement of hit efficiency / MIP light yield
12) Discriminator only running mode (removes 5.7us dead time, and all light data) - (lower priority can run without).
  • Develop Firmware/Readout/Unpacking.
  • Calibrate.
  • Repeat efficiency study with discriminators only.


  • Integration of Vesda spoke detector into interlocks.
  • Finish interlocks

Cryo Leaks (led by Craig next few weeks)

  • All are very small but still should be addressed. - ALL LOCATED
  • Mark T has helped Craig to locate all leaks through system. TBC next week. - DONE
  • Craig needs to turn the cryos off to fix the leak. This should be included in the schedule.

For Mock data challenge 2 (led by Ed, Craig and Melissa)

  • Integrate tracker into controls and monitoring.
  • Fix local ground?

SW and Analysis readiness (led by Melissa)

The following to be completed by May.

  • Fix data unpacking.
  • Integration with CDB - Chris Heidt
  • Final track fit Kalman and pattern recon. - Chris Hunt
  • Online reconstruction (50% complete and enough for mock data challenge 2 but 50% more for step IV). - MU
  • Efficiencies
  • Alignment
  • Analysis run plan.

Updated by George, Melissa over 7 years ago ยท 10 revisions