sPHENIX discussion of the superconducting solenoid

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

Present: Mike Anerella, Ray Ceruti,  Achim Franz, Paul Orfin, Winston Pekrul, Roberto Than, John Haggerty, Edward O’Brien, Brian van Kuik, and Kin Yip

 

https://indico.bnl.gov/event/11319/

 

1. We first discussed whether we’d want to test the “pressurized lines” with helium mass spectrometer.  Ray Ceruti explained to us that the pressurized line in the extension doghouse is in a state that it’d fit with the Valvebox (from the top) perfectly.  To test the pressurized line with the Valvebox, one needs to do quite a bit of surgery to create interface for such test.  It’s painful and also risky as it’d need to be put back to the state that it can just accept the Valvebox after the test.  The connections have been cut a couple times during the low-field and high-field tests and need to be cut and fit again for the final installation.  To do a test in the Assembly Hall without the Valvebox is disruptive.  And people didn’t think/believe that our careful transportation could damage the internal pressurized line.   ( Ray asked whether it’s possible that we can put on Valvebox without the platform and John Haggerty showed us some pictures from the ESRC reviews.  This seems just unlikely. )
   
   
2. Paul Orfin then suggested an easier test of just testing the insulating vacuum line which may require a new flange and ~an additional week of pumping for this test.   After some discussion, it’s felt that this test doesn’t prove too much in addition to giving us a warm fuzzy feeling, for a system that has been tested in the low-field and high-field tests. 
   
   
3. We therefore conclude that we don’t do any cryo/vacuum test in the Assembly Hall before the Valvebox (which is necessarily sitting on the platform) unless we observe any “unfortunate” incident(s) during the transport from 912 to 1008.   John Haggerty and Paul Orfin’s group will install their accelerometers to detect any vibrations.  Paul Orfin said that his ‘safety’ prescription is that anything < 3g is good and nobody voiced any objection for that.  John Haggerty showed his record of accelerometer data from California to BNL (https://brookhavenlab.sharepoint.com/sites/sPHENIXMagnet/External/Shared%20Documents/BaBar%20Documents/babar%20shock%20time.pdf) and it’s was < 1 g all the time and < 0.5 g most of the time.
   
   
4. It’s further decided that we will do the full pressurized test with the Valvebox installed on the platform after we roll the entire sPHENIX assembly into the Expt. Hall, unless we are way ahead of schedule  and  in that case, we can do the pressurized test in the Assembly Hall.
   
   
5. Ray Ceruti shared a bit of steps in the assembly of the Valvebox.  He said that we try to pressurize the Valvebox a bit and sniff for any helium leaks, before the MLI (multi-layer insulation) is put on and before we  close the door of the Valvebox.
   
   
6. Russ Feder and Carl Schultheiss didn’t join us.  I just mentioned the plan for the two talks in the ESRC review that Carl would present the operation (ramping to full current), power supply and quench detection, like his presentation in the last I&F 1008 review but safety in mind this time.  Russ would cover the general safety.  I talked with Russ before the meeting that he’s going to fill out the green-sheet/work-permit form so that we’ll be able to cover all safety concerns.
   
   
7. At the end of the meeting, Roberto Than reminded us that we have to make sure that the actual ODH for the 1008 Experimental Hall will be done.   We understand that Jonathan Reich’s Access Group will install the ODH system and Peter Cirnigliaro will make the USI evaluation.  This was covered in the last ESRC review (Apr. 9, 2020) and so we don’t need to talk about it again in the coming ESRC review (dry run on May 3 and actual on May 17).
   
   
8. After the meeting, I talked with Jonathan Reich who is the Access Control Group to remind him about the ODH sensor in 1008 for the sPHENIX Magnet.   ( In fact, he’s incorporating the ODH for Tandem at this particular moment. )  He’s prepared to do this for 1008 and their group is making a new system for RHIC anyway.   I talked with Roberto and he’s agreed to pass his ODH calculation and the “recommended locations” for ODH sensors (3 of them) to Jonathan Reich, and this mailing list.