Wednesday, July 27, 2011, 12:58: 

Target length = 11.2cm

Total UC2/C foils = 245 discs

Total U/cm2 = 15.27g

Target has been pumped down over night,  Vac currently @ 1.64e-6 Torr.  BP @ 38mT.

TGHT @ 76A/0.27V.  Vacuum went up slowly to 4.8e-5 Torr.  TGHT brought back down to 68A, vacuum is holding at 4.8e-5 Torr. 

Wednesday, July 27, 2011, 14:43: Vac @ 2.3e-5 Torr.  Start auto-heating.  0.5A/min, TGHT max = 525A.

Sunday, July 31, 2011, 10:43:  TGHT has reached to 525A.  The pressure came down when the heater was stable at that current (see attachment: striptool_july 31); this implies that more power is needed to finish the carbonization process.  Peter Kunz was informed, and we decided to increase the target heater to 580A.  I will continue to monitor this from home. 

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On Aug 01, Peter and I agreed to increase the TGHT to 600A (see attachment: striptool_july31_600A) .  Based on the heating curve with 3 Ta-heat shield @ 600A, the would give ~ 2050C/3700W (300C/1600W more than UCx#2).  By looking at the striptool, the pressure came down soon after.  More power might be needed to finish the carbonization process; however as per Peter the graphite vapour pressure increases above 2000C, and we don't know what will happen above that temperature.  So, we will keep it at 600A until the pressure comes down to low 10e-6 Torr.  Then I will being the auto cooling.  Anyway, we are running at 580A online.  On the safe side, 600A may be enough for the conditioning.   

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 Tuesday, August 02, 2011, 11:19:  TGHT has reached to zero current (see attachment: UCx#2_conditioning).  The evaporator will be vented with Ar.

 Friday, August 05, 2011, 10:49

Unfortunately, after the evaporator was vented with Ar, the target was found be be broken into 3 segments. More details later...