Dear,
Here is a summary of CREAM-IV flight preparation status on the 12th of November at McMurdo.
- TCD problem with the PMT#4/5 HV resolved by reconnecting the 12 V power line to the HV PS which was cut during the HSK circuit modification.
- After that the hkconv4.dat file modified to have correct value in TCDPwr12. The new hkconv4.dat file will be updated into the relevant computers.
- TCD dead time debugging started this morning. A few investigations tried.
- Modified the time out from 100 ms to 25 ms in case when the event number re-sync. happened. Added printf function to make sure that it is working as it supposed and confirmed.
- Checked the CPU latency by looking at the Master Trigger Trigger Output during the muon trigger run. It seems that the maximum is less than 7 ms. So the 25 ms is quite safe to use for the time out.
- During the test, in the ELo=ZLo trigger, there were quite number of errors coming in event number mismatch when all sub-detectors are on. It seems that it is related with the TCD triggered events. Tried with only calibration trigger and error rate seems very low and normal. To investigate this further, decided to tune the TCD trigger threshold values since ZHi is higher than ZLo.
- During the TCD debugging, the Chercam HSK problem with a pin corresponding about 10 channels were investigated. It turned out from a loose connector in the HSK connector on the top I/O board by Antje. Replaced the too long screw with a shorter one and the HSK display becomes normal. Great news since we do not have to make a new connector or cable. At the same time, other connectors on the HSK top I/O board are checked and replaced and/or tightened if necessary.
- Looked at the tSCD data in charge calibration run. It seems that two sensors have bad connection and show mostly zero gains. Will investigate tomorrow in more details.
- Tomorrow, we will work on the followings before the CPT.
- TCD code modification and test including TCD threshold value tuning.
- Investigation of tSCD for some of bad channels in the data which we saw from time to time during integrations.
- Calorimeter MB#7 temperature sensor problem check. If the temperature sensor is bad, will replace with a spare board.
Cheers, MooHyun.
