Minutes of Weekly Transversity On-site Meeting
[Mar 27, 2006 (Monday) at CEBAF B101 (10:00-10:20 am)]
Attendee:Brad Sawatzky, Todd Averett, Kalyan Allada
Recorded by Lingyan Zhu

1. Target Vertical Coil Design Progress
   Jen-Chieh, Jian-ping had some discussion with Al about the design 
of the vertical coils. They will be a pair of big coils that can be 
installed without taking apart the existing coils. Todd, Jian-ping will 
discuss more with Al about some details of the design.

2. Target Lab Progress
http://hallaweb.jlab.org/physics/experiments/he3/target/html/logdir.html
   A. (spin reversal) Huan wrote "Reverse Spin Technote", which states that 
the spin flip every 10-20 minutes will lose 10\% polarization. 
http://hallaweb.jlab.org/experiment/transversity/target/spin_flip_technote.ps
or
http://www.jlab.org/~hyao/pdf_files/He3_Target/spin_flip_technote.ps
   B. (gen) A large chamber he3 cell (Edna) was installed to replace Dolly.
For Edna, the potassium to rubidium ratio is 5:1. (halog--167856)
According to Nilanga's run coordinate report, the preliminary
NMR measurement indicated that the polarization was as high as 58\%. 
Todd commented that large pumping chamber may be the way to go in terms of 
achieving higher polarization. Aiden observed in Gen that the higher oven 
temperature led to faster spin-up  though not necessarily higher polarization.
We might need to re-design the existing oven to 
accommodate large chamber hybrid cell or higher oven temperature.
Todd commented that the discoloring of the cell is due to the radiation damage
on the glass. It has little effect on the target performance at beam current 
around 12 uA.

3. BigBite Progress 
   A.(gen) The online momentum calibration for the BigBite gave a momentum 
resolution of about 1\% in sigma. (Nilanga's run coordinate report).
   B.(TDC test) Brad will have some time to test TDC this week.
   C.(space) Doug found some space in the testlab for BigBite about Gen.

P.S.
Transversity Collaboration meeting is coming on Apr. 11, 
joint with the polarized he3 meeting on Apr. 10.