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User name Jin
Log entry time 22:03:26 on January20,2009
Entry number 257048
keyword=G0/TIR helicity problemHelicity G0/TIR signal has a problem. 90% of events which should have helicity = +1 is read as helicity = -1.
This problem was first observed in run 5346, 9:54AM this morning in the morning. Rebooting TS11 before run 5393, didn't solve the problem.
However, the ADC helicity signal is OK. And the scalar gating is fine too.
Therefore, the preliminary guess would be the helicity signal cable going to the LHRS TIR is getting loose. However, since the ADC copy is still working, there is no need for immediate repair. It will be good to fix during next access.
FIGURE 1
