1. Preliminary result of the target polarization 2004 Kaori Kondo COMPASS target team

2. upstream cell downstream cell Polarization measurement 2004 120  30 mm 60 mm  15 mm outer coil inner coil (coil 6) Coil 6 does not work.

3. magnetic field direction NMR signals negative polarization positive polarization (spin anti-parallel to the field) (spin parallel to the field) always monitored!

4. building up polarization relaxation time day polarization (%) typical polarization buildup 1 day : +42% & -40% 2 days: +47% & -46% 3 days: +50% & -48% 5 days: +52% & -49% at 60 mK 2.50 T (normal frozen mode) 15000 hours at 60 mK 0.42 T (transverse mode) 1400 hours lost 0.7 % in 2 weeks lost 2~3 % in 5 days

5. TE calibration Period Temperature (K) 5 May ~ 7 May 1.52 7 May ~ 9 May 1.28 9 May ~ 12 May 1.17 9 June ~ 12 June 1.00 12 June ~ 14 June 1.32 1/T signal area unit upstreamdownstream We had very good calibration with 5 temperature points. Errors from TE calibration can be about 1%

6. TE calibration relaxation time measurement 2 Aug. cooling water pressure 20 Aug. cooling water stop transverse thanks to Isabel upstream downstream

7. H E L P ! ! We would like target shift crews 21 Sept. ~ 4 Oct. Experienced people are welcomed. Still 13 shifts are not occupied. Have a look on: http://compass-target.web.cern.ch/compass-target/ -> shiftlist.http://compass-target.web.cern.ch/compass-target/ Contact with Fabrice Gautheron for volunteering! Fabrice.Gautheron@cern.ch