controlled access work in Left HRS

NEXT
Make New Entry, Make Followup Entry

User name Ramesh/Vince

Log entry time 03:19:22 on November 05, 2009

Entry number 297453

keyword=controlled access work in Left HRS

Vince and I took controlled access to troubleshoot the trigger issue with
the left HRS (Diancheng and Xiaoyan went to the right HRS for other work
in the same time). We found that the retiming signal was before the L1A
(which is against the prescription that retiming needs to be about 40 to
60 ns later than L1A). Diancheng recalls that the prescription was
followed and retiming was set that way; not sure why we see retiming
before the L1A now. We set the retiming 60 ns delayed with respect to
L1A. Took a new run and found all histograms normal. We were even more
happier that the double peak structure in S1 and S2 TDCs now disappears;
no second T0 in VDC too. Everything looking normal, we called off
controlled access to go to beam permit.