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

From: Chris Crawford (chris2@lns.mit.edu)
Date: Mon Nov 08 2004 - 11:51:52 EST


hi adrian,
  thanks, and you could also be sure to put in elog which runs started
with the both new Voltage settings?
--thanks, chris

Adrian T Sindile wrote:

> Hi, Chris!
> The only tube that seemed to go consistently down was RTOF3 top (not
> bottom as I had written)... that was consistent with your efficiency
> finding, so I put an extra 50 volts on it.
> LTOF5 bottom (and others) seems OK in the raw flasher ADC check that I
> do for stability only (it also looks OK on the online GUI if I
> remember correctly) but I just added 30 volts per your request (it
> cannot hurt).
> When the HVGUI is rebooted, it will read from the database the new value.
>
> Adrian
>
> On Mon, 8 Nov 2004, Chris Crawford wrote:
>
>> hi adrian,
>> what do the other diagnostics like adc's say? i not sure about my
>> results yet, so maybe you could just raise ltb5 by 50 V, and wait on
>> the others.
>> --chris
>>
>>
>> Adrian T Sindile wrote:
>>
>>> Hi, Chris!
>>> I could change the voltages on all those tubes, but like John said,
>>> we might mess up the timing... from your initial plot I thought only
>>> RTOF3 was bad enough to require intervention...
>>>
>>> On the other hand, if gains are going down, maybe putting them back
>>> by adding about 30 volts would not create that much of a timing
>>> shift... just let me know if you think it should be done...
>>>
>>> Adrian
>>>
>>> On Sun, 7 Nov 2004, Chris Crawford wrote:
>>>
>>>> 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).
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>



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