Minutes from weekly target meeting 4th of September 2003 in 888

a) Isabel presented analyzes of the 2003 polarization data. Two buildup periods
were analyzed. In May 13 - 23 the buildup time was about 54 hours for upstream
negative polarization and 47 hours for downstream positive polarization.
In June these were about 44 hours for upstream positive polarization and 
42 hours for downstream negative polarization. In frozen spin mode at 2.5 T
the polarization decay time was about 30 000 hours for positive upstream
polarization and about 17 000 hours for negative downstream polarization.
At 0.5 T in transverse frozen spin mode the decay time was about 1500 - 2000 
hours. The stability of the Q-meter parameters was also studied between June
20 and July 15. The baseline center frequency, line width, gain and quality
factor were plotted versus time for each coil. The drift in the center 
frequency in this period was estimated to produce maximum 0.8 % (coil 6) 
change in polarization - for other coils typically < 0.2 %. The drift of gain
was estimated to be typically 4 10^-3/h giving in the one month period
about 1 % total drift.

b) Kaori checked the zero field deuteron relaxation time to be about 17 - 21 
minutes. The coil #7 was used since it was closest to zero field. During
the relaxation the deuterium and 7Li do not seem to follow the same equal
spin temperature curve that was checked in 2001.

c) Yuri estimated the 2nd moment of deuterium NMR lines by fitting a Gaussian
line shape to the NMR signals. The 2nd moment seems to depend on microwave
power, which is surprising result since the density of F-centers is small
about 10^-4 - 10^-3 per nucleus. Yuri suggested that the 2nd moment could be
used to check the correct tuning of the microwaves. The polarization 
dependence of 2nd moment data seems to follow the theory of Abragam.

d) Fabrice reminded that the physics run will end on September 17. Few shifts
on the last week are still empty. There was also discussion about the physics 
data taking during the field rotation.

e) Norihiro showed plot on cooling power data using TTH4. Also the cooling
power normalized to the 3He flow was shown. The curve starts to deviate from
ideal behavior below 200 mK. By comparing the cooling power curves with
TTH1 and TTH2 difference in cooling powers between upstream and downstream
can be seen. Norihiro estimated also the temperature of incoming 3He to be
190 mK when the mixing chamber is at 60 mK. The heating due to muon beam was
estimated to be about 1 mW. The heat leak due to radiation and gas conduction
was estimated to be below 0.2 mW.

f) Jaakko showed a plot of 7 deuterium NMR signals with polarizations +8 %, 
+15 %, +20 %, +30 %, +35 %, 40 % and 45 % superimposed on each other. The
signals were shifted and scaled to same size and same center frequency.
There is no significant difference in lineshapes and thus the nonlinear
corrections can be expected to be small.