NEXT
User name Peter L
Log entry time 02:04:31 on June15,2004
Entry number 125804
keyword=Scanner runs note
We began by ramping up our PMT's to previously decided mnominal
voltages. This was done in the high voltage panel leCroy HV. In the
right arm bottom "slot 10 shower" channel 11 -> -1650V , Left arm
"5th pion rejector" channel 11 -> -1300V.
Next we started a scan (run 2139) at (17,57)(cm) and moved down to
(17,10) ->(14,57)->(14,10)->(11,57)->(20,57)->(20,10)->(18.5,10)->(18.5,57)
->(15.5,57)->(15.5,10)->(12.5,10)->(12.5,57)->(11,10) then back to
(17,57) for the next run.
Run 2140 we cycled from (18,57) to (18,5) at different PMT voltages
to avoid saturation in the right arm. We settled at -1550 in the
right and -1400 in the left. Events are as follows:
right run 2140
1600V 9500->14000 events
1550V 15000->18300 events
1500V 18300->21700 events
We decided that -1550V was the best and will therefore remain the nominal voltage for the right side. Left we raised to -1400V.
next entry will contain plots.