Minutes from target meeting held September 30 2011 in 892-2-009

These minutes are available also from:

http://wwwcompass.cern.ch/compass/detector/target/Minutes/2011/

a) Tatsuro: stop polarization build up on Friday evening 22:00. Polarizations
of -88.1 %, +86.5 % and -86.8 % reached. In frozen spin mode on Tuesday
morning fill the check list at 8:00. At 8:54 the roots #4 stopped. The
motor protection circuit breaker was reset at 9:18. The mixing chamber
heated up during the pump stop and the polarizations dropped to 
-76.2 %, +70.3 % and -68.5 %. Restart polarizing from 10:30 after field
rotation to positive solenoid current. Access was needed to balance the
microwave power between the upstream and downstream cells. On Wednesday 
evening 22:00 polarizations -88.1 %, +86.5 % and -86.8 % reached. Frozen 
spin mode started. The weight of the LN2 buffer dewar is 285 kg when full.

b) Kaori: retune the coil #4 Q-meter on Friday September 30 afternoon.
After retuning the polarization measured by this coil shifted by 0.6 %.

c) The thermal equilibrium calibration after the run with the target material 
and empty target cells was discussed. After this some additional time is 
needed for the magnet tests. The target unloading is planned on Tuesday
November 15. Yuri: magnet field map should be measured with all the trim 
coils off. 

d) Fabrice: offer received from the ET systems for eight new trim coil
power supplies. The old power supplies can not be repaired any more.

e) Yuri reported on the PSTP2011 that took place in St.Petersburg Russia
September 12 - 16. See http://pstp2011.lkst.ru/

f) Jan told about proton relaxation time measurements of deuterated etanol
and butanol done in Prague using 500 MHz pulsed NMR spectrometer.

g) Jaakko: frozen spin field maps before and after retuning of the trim 
coils
http://wwwcompass.cern.ch/elog/target_polar/138

h) Jaakko: NMR-peak shift during the polarization build up of September 
22 - 23: 
http://wwwcompass.cern.ch/elog/target_polar/139