sPHENIX discussion of the superconducting solenoid

["Yip, Kin" <kinyip AT bnl.gov>]

Agenda/powerpoint : https://indico.bnl.gov/conferenceDisplay.py?confId=3470

 

 

(1)   We looked at D. Phillips latest layout :
https://indico.bnl.gov/getFile.py/access?sessionId=0&resId=0&materialId=4&confId=3470

In addition to the staircase moved to the Lead-End, the DAQ, power supply and dump resistor locations have been swapped to maximize
the cable length (to reduce the time-constant L/R).  So, now, DAQ is the closest to the Lead-End of the Magnet.

Paul Orfin told us that their Cryo pipes need to go over the power supply or dump resistor.   Jim Mills asked whether there will be condensation problem.
Paul told us that in principle those are “warm” but they’ll keep an eye and possibly install some gutter to prevent liquid dripping to the power supply.

(2)   We then discussed about the status since Ray Ceruti closed the doors for the junction-box at the Magnet/Extension end.  We’re rigging power supply,
dumb resistor, concrete blocks, which have been moved closer to the testing site but not yet there.

(3)    Then, we talked about my optimistic scenario:

In the coming week(s),

=> Install end-walls/roof-steel (more challenging due to the absence of J. Hock)

=> Move power supply/dump resistor & concrete blocks for the platform

Then, we nstall the “Valvebox Platform” (concrete)

ð  D. Phillips hopes that the platform and hand railing will be installed by next Wed. Aug. 23 (if we can have the carpenters …)

=> Staircase to be delivered Aug. 23 – 28 (?) hopefully

=> Install staircase/railing (the week of Aug. 28)

=> Possibly install Valvebox on Sept. 1 or the week of Sept. 5

=> Cryo piping/connection installation for ~4 weeks (possibly shorter)

    which can possible be shorter as some work already started and there may be more people available.

=> Cool-down by the end of Sept. (???)

=> If we’re “lucky”, High-Field Test may start in mid-Oct. if cool-down takes only ~2 weeks.

Paul couldn’t be too sure about the 2 weeks’ cool-down time but he didn’t think it’s impossible.

(4)   John Haggerty then told us about the Director’s Review’s action item.

The first three (mainly from G. Ganetis), about magnet susceptibility to RHIC beam pre-fire, external review for the cryo-system tapping into RHIC,
and the presence of snubber circuit to avoid noise,  are either something that we’ve had or something which probably requires explanations.

The more difficult recommendation is for the magnetic field mapping for the TPC region.  John and Achim Franz think that we may not need the mapping
but we need to study to see whether we need field mapping or not.  I’ve extracted some 3D field mapping from Wuzheng’s model which uses a packing
factor to account for the HCAL plates and the gaps.   Depending on what the future investigation will lead, we may need to implement the complicated plates
in Opera (or other software) which will need help from some experts as Wuzheng Meng has retired.

 

(5)   Jim Mills asked whether we need to review the “Run Plan”.   We told him that the “Run Plan” has been reviewed in this meeting and also offline.   Joe Muratore
has modified it more than once.    Carl and Joe may still modify it and the procedure may be modified during the test.