sPHENIX discussion of the superconducting solenoid

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

Hi,

Just for comparison, dividing the sPHENIX magnet into half (using the model 
with poles as shown in the .pptx), 
Wuzheng has quickly calculated the force to be 5.651E6 Newton = 
5.651E6/9.8/1000 = 576.6 metric-tonnes, this
is like only a 50% increase over 380 metric-tonne in the original Babar, 
~acceptable in Pasquale's
limitation boundary. 

Dave said sending out this might make somebody sleep better and so I send 
this ...

Kin

-----Original Message-----
From: Meng, Wuzheng 
Sent: Friday, March 27, 2015 3:33 PM
To: Phillips, David B; Yip, Kin
Cc: Makdisi, Yousef I; Meng, Wuzheng
Subject: sPhenix forces on each half coil-package

Dave/Kin, 

Upon your request, I calculated magnetic forces on each part of the coils, by 
using the new geometry received in January (from a meeting called by Achim); 
except I did not make cuts on the south end yoke. 

As you know, BaBar solenoid has several different current densities in order 
to achieve relatively flat Bz field along the axis. I have to further divide 
them (split them in the center), so that I can calculate forces on each half. 

Attached ppt file is the summary. The net axial force on each half coil 
package is about 577 Ton, pointing to the center of the magnet. 

Please comment.

Best wishes,
Wuzheng

Attachment: sPhenix_coil-forces.pptx
Description: sPhenix_coil-forces.pptx