Re: [BLAST_SHIFTS] Shift summary 11/06/2004 B (9-17)

From: Chris Crawford (chris2@lns.mit.edu)
Date: Sun Nov 07 2004 - 11:24:44 EST


hi adrian and john,
  i was also a little concerned about ltb5 also (and ltb9?). first
from scalers, second from the yield plot. (left tof 4 is higher -> left
tof 5 is lower) i expect a discontinuity between tofs 3,4 but not 4,5.
finally, the eff plot still has problems, but you can see the same
discontinuity in the magenta curve between TOF's l4 and l5. it might
not be a big problem, but if we could add cerenkov's of opposite sector
into the singles 'trig==7' trigger, then we could have a constant
monitor of all of the TOF efficiencies.
--chris

      ltt ltb ltc rtt rtb rtc

 0 3337, 3736, 2866, 5237, 3567, 3357
 1 4118, 3046, 2813, 3107, 3213, 2448
 2 2849, 2541, 2193, 3035, 2618, 2257
 3 2307, 2444, 1793, 1188, 1786, 1107
 4 2805, 3123, 2022, 3209, 2314, 1980
 5 2469, 564, 561, 1767, 1369, 1137 <<<<<
 6 1391, 2132, 1199, 1366, 2081, 1166
 7 1885, 1479, 1099, 1509, 1267, 972
 8 1391, 1800, 1039, 1671, 732, 695
 9 1514, 369, 367, 1042, 980, 681
10 1607, 1636, 974, 663, 975, 548
11 2875, 3621, 1904, 1909, 3069, 1248
12 1878, 2594, 1232, 987, 2706, 854
13 1825, 1447, 867, 2141, 2002, 1045
14 2426, 1721, 665, 1436, 2684, 1056
15 2192, 2790, 1210, 2305, 563, 530

John Calarco wrote:

>Need to look at TDC offset for RTOF3 now. Adding 50V should have caused
>the transit time in the PMTs to be reduced. By how nuch? This is a
>change of V of dV/V ~ 50/2500 = 1/50. Transit times are ~ 30 ns. So
>were talking 0.6 ns ... rounds off to 1 ns.
>
>
>
>On Sat, 6 Nov 2004, Electronic Log Book wrote:
>
>
>
>>Operator: adrian
>>
>>Runs 12373-12382 taken. Crunching...
>>Run 12377 is shorter (CODA crashed - rebooted ROCs remotely).
>>
>>RTOF3 shown in Chris' recent efficiency picture seemed to have a problem. I tracked it down, the scalers for the bottom tube were consistently lower. Other tubes seemed lower too, but an ADC study of the recent hydrogen runs showed only RTOF3 bottom to be going down continuosly.
>>Added an extra 50 volts on that tube during run 13282 (and Aaron rebooted HVGUI right after that run, so the changes should have taken effect).
>>
>>
>>
>>
>>
>>
>>
>
>
>



blast_yield.gif

tof_eff_wc_3.gif



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