sPHENIX discussion of the superconducting solenoid

[Kin Yip <kinyip AT bnl.gov>]

Hi,

Pablo Rosas (from C-AD) gave a presentation about the power supply (for sPHENIX Magnet) this afternoon for more than 1 hour from 3 pm,
in front of D. Bruno, J. Galarraga, I. Marneris, J. Sandberg, C. Schultheiss and myself.     This is about what he's been doing and what he'll
do, the schedule etc.

I've placed his powerpoint here :

https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Past%20Presentations/2016-7-22%20sPHENIX%20Power%20Supply%20review.pptx

It contains many drawings/circuit diagrams that Pablo  has made for this power supply --- like what he's done for other power supplies in C-AD.

People have made some suggestions such as doing hipot before the power test, finding another magnet with higher load (more than what he's
got ~750 A), running current over the dump resistor to test, adding DC output over-voltage protection etc. etc. that Pablo has noted himself.

The power supply has output ~20 V and 5000 A.   It's mentioned to me again that its output regulation (or fluctuation) is ~0.01%.  
This probably means that the B-field has a stability or instability of ~0.01%.  This was what BaBar has lived with.   ( So, it's good enough for us ? ) 
I've never heard of any physics requirement on the B-field [ but I'm quite ignorant :-)  ].     I've sent an email to John Haggerty about this.

Kin