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HERD prototype beam test 2021 issues

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Travel issue

Beam schedule could be found at the beam coordination page.

For HERD, its:

  • at SPS H4, from Oct. 13rd to Oct. 20th.
  • at PS T9, from Nov. 1st to Nov. 7th.
The probabilities of Chinese colleagues could be present on beam site is limited, due to the local administration regulations and the CERN host states policies.

There're three options if we follow the current beam schedule without cancellations.

  • full prototype tests (500 LYSO[IHEP] + TRD + PSD + SCD + FIT). The European colleagues take full operation of each sub-detector while the Chinese colleagues will participant online remotely.
  • absent of hardwares from China, but with small CALO prototype (30 LYSO[Florence] + PSD + SCD + FIT).
  • absent of hardwares from China, without any kind of CALO prototype. (PSD + SCD + FIT)
This following page illustrate the alternate actions by the European colleagues if the Chinese colleagues can't be present on beam site, while all hardwares from China will be sent to CERN( around Sep. 10th) for the joint prototype beam test.

Discussion of the alternate actions

A summary table which was organized by Chinese colleagues could be found as following, includes the procedures of several major on-site operations.

These operations are expected to be implemented with the help of the on-site European colleagues, while the Chinese colleagues will provide manuals(paper, video) and real-time online assistance.

It'll be necessary we firstly to evaluate the possibilities of these alternate actions, and the manpower is sufficient or not.

  Items short description and when to act operation catalog disassembly and then assembly the instrument after shipment, operations necessary or not difficulty level (extremely, hard, advanced, tricky, easy) training time needed on-site Chinese needed or not, for translation on-site manpower needed
Crystal array special packing 1). disassemble the special packing surrounding CALO at the assembly stage;
2). install the packing back immediately when the tests finished( the action should be done before CALO protortype transported to the beam buffer zone )
mechanical install and de-install necessary easy < 1 day no >= 4(at the assembly and packing stage)
calibration scan the LYSO array for equalization study by taking use the global table. The equalization is scheduled at the beginning of the run and at the very end of the run. beam and general table operation, synchronization not necessary easy < 1 day no 1 per shift(real-time operation during test)
Trigger system DI2C joint test DI2C synchronization protocol and hardware.update firmware remotely after the joint test at the assembly stage.parameter tuning at the early run stage. computing setup,
hardware/parameter tuning,
beam operation and synchronization
not necessary. Only cable connections easy 1 day probably real-time cooperation during the assembly stage
switch neutral filter if the signal intensity is not appropriate, disassemble the trigger box, switch the neutral filter with a new one and then coupled with the trigger PMT. This action will only be necessary at the early run stage and lasts a few hours. precise mechanical de-install and install probably necessary hard 2 days probably 2(operation once or twice at the beginning of the beam run)
adjust trigger PMTposition if the signal intensity is not appropriate, adjust the trigger PMT to pre-defined postions by a handle outside of the crystal array. The operation may take a few iterations for a proper attenuation ratio mechanical tuning not necessary easy 1 day no 2(a few iterations and tuning at the beginning of the beam run)
backward calibration mute the beam and then send command to the trigger system, several times/day during the full beam data taking week . beam operation and synchronization not necessary tricky <1 day no 1 per shift,can overlap with the requirement of calibration
IsCMOS camera optical fiber and taper alignment due to the vibration in transportation, there is a position deviation between the fine installation interfaces between the fiber and the optical taper. An alignment procedure is scheduled to fine tune(10um accuracy) the positions between the optical fiber taper and fiber panel after the arrival of equipments at CERN. super precise mechanical operation necessary extremely there is NOT a 'standard' procedure. The XIOPM senior engineers is trying to figure out a possible solution for remote guidance solution needed >=2(at the assembly stage)

the taper will be fixed coupled and the alignment action will no longer be necessary
power supply system the power supply system of the camera is quite complicated, any kind of mis-operation will result a termination. For secure consideration real-time confirmation of each power operation will be necessary between people on-site and XIOPM engineers. full and real time power control not necessary hard 4 days no 1 per shift,>= 3 electronic engineers (full cover the whole week of the test)
power supply system the power supply system is optimized with remote control. On site operation only include the cable connections. Once cables are well connected, remote operations by Xi'an experts with internet will be the first choice, on-call electronic expert will be necessary in case of internet problem and other issues. cable connections, computing setup not necessary easy 2 days no 1 at the assembly stage, 1 on-call expert during the beam taking week
acquisition card and storage server the data acquisition card and storage system will be shipped separately from the main computer. The computing setup and tuning will be necessary at the assembly stage. computing setup not necessary tricky 2 days no 2, at the assembly stage
TRD detector chamber gas leakage test connect the detector pressure sensor interface to the computer to check whether the detector chamber is leaking. If the detector chamber leaks, switch the detector to the flow circuit; if there is no leak or the leak rate meets the requirements, the closed-gas detector is still used for testing. The leakage test and switch will be only necessary at the assembly stage monitoring, mechanical operations not necessary easy < 1 day no 1, at the assembly stage
detector interface connection connect the detector's high-voltage line, front-end electronics, back-end electronics, and computer at the assembly stage and finished stage cable connections, computing setup not necessary easy < 1 day no 1, at the assembly stage
noise reduction hardware parameter tuning and real-time monitoring at the assembly stage and lasts around half a day. hardware/parameter tuning, not necessary tricky < 1 day no 1, at the assembly stage
real time access during the beam data taking, remotely connect to the computer to perform beam fetching operations will be necessary, and on-site shifters will be asked for such kind of help and operation. real time computing operation not necessary easy < 1 day no 1 per shift,can overlap with the requirement of calibration
General structure platform Assemble seven sub platforms to the common general table, test all functions(2d scan and rotate) at the assembly stage. Install each sub detectors(PSD, CALO, TRD, FIT, SCD) on the general table, and align them to the beam at the assembly stage. mechanical install and de-install not necessary tricky 2 days no 2+2(2 for the global table mechanical installation, the other 2 for the remote control electronics setup, at the assembly stage)
packing box open the packing box before test,pack up all devices in to the same box after test mechanical install and de-install necessary easy < 1 day no >= 4,can overlap with crystal packing (at the assembly and packing stage)
the assembly stageIn general, the whole test beam could be divide into three phases and the corresponding manpower needed for these alternate actions is more or less likely:
    • >=4 persons(mechanical activities), for general structure installation, crystal array installation.
    • >=2 persons(computing and electronics activities), for IsCMOS, TRD, trigger cable connections and computing setup.
    • >=1 person(electronics activities), for TRD parameter tuning.
    • >=1 person(electronics activities), for joint trigger test.
  1. the beam running stage
    • >=1 persons(electronics activities, at least 1 person on call), full cover the test period, for IsCMOS HV operation.
    • >=6 persons(mechanical and electronics activities, 2 persons on site real-time), for general structure operation, calibration operation, trigger DAQ operation, TRD access.
  2. finishing stage
    • >= 4 persons(mechanical activities), for the immediate crystal array re-packing job.
    • for other de-install job, manpower is not a problem since we're not in a hurry.

      -- xu ming - 2021-07-17


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Topic revision: r9 - 2021-09-23 - XuMing
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