From: VAXGS::BRAJESH
Subject: MACRO-USA SHIFT REPORT: Nov. 2nd to 13th.
Date: 16-NOV-1998 15:21:17
Expires: 1-DEC-1998 15:21:17
MACRO-USA Shift Report (Nov 2nd to 13th)
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PEOPLE PRESENT IN THE DETECTOR AREA: BCC, FC, EK, IK, VM, MO, NZ
PEOPLE PRESENT OUTSIDE : SK
Everything looked fine when I came on shift.
Run 16624 on 02-11-98 crashed after 260 mts because power supply on PISA
SM1 had problem. Power supply replaced and next run started with no poblems.
TOTAL TIME LOST = 6 to 8 minutes.
Run 16625-16632 (8 runs) for 47 hours 20 minutes (from 10:40am/02-11-98
to 9:55am/04-11-98) went without any problem. Tells you about the
stability of the detector and DAQ system.
Run 16633 stopped after 37 minutes for maintenance/calibration on 04-11-98.
No calibration could be done for several hours because folks were working
on high voltage maintenance/replacement.
NO GLOBAL DATA TAKEN FOR ALMOST 8 hours. This is now common almost every
wednesday. We do not take global data with four SM's while other two are
calibrated.
High rate was observed for monopole triggers on
02 nov - 2B13, 3T06, ----, 4T02, ---------, 4T17, 5T02-T03, 5T05-T06, 6T02.
03 nov - 2B13, 3T06, 3T12, 4T02, 4T10-4T12, 4T17, 5T02, 5T05, 6T02.
On 2nd nov only 4E08-4E11 were dead but on 3rd nov 5T03 has been added.
Most of these are known and will be taken care of.
Both PMT's replaced(04-11-98) on side 0(zero) of counter 5T06.
Rate has gone down. It seems that the the rates could be higher due to
spark near the PMT's because mylar was not placed properly. It is not
definite that there was a problem with PMT's.
Following calibrations were done on SM3 and SM4 (04-11-98):
1. Special TOHM cross-talk calibration. RUN 91205. Counter 4E11-1 was
broken in ERP only. PHRASE in muVAX2 was also read at the same time.
***SOPHIA Kyriazopoulou has looked at the cross-talk data
and her preliminary analysis is given below.***
"""We have performed a quick calibration to get a feeling about how
big is the effect of TOHM crosstalk with LED events.
I analysed some of the old Lamossca Calibration runs , since
they have events where LEDs are fired to produced big pulses.
During these runs only the LED of one end of the tanks were fired.
In addition a new run was taken in SM3 and SM4 firing the LEDs at both
sides of one tank. The highest LED setting (8Volts) and various pulse
widths were used (1,2,5,10 microsecs).
The mean of the amplitude dirtibution of the pulses
generated like this at both sides was around 3.5 volts.
The integral (above 100 mV) of the LED pulses (integral of two sides
added) the WFDs recorded reached 50V microsecs for some tanks . No tank
had received pulses with less than 15 Vmicrosecs.
The number of events with extra SMT hits was around 80 out of total
2464 events and seem to be consistent with the background.
The occurance of the extra SMT hits didn't show obvious strong
dependance on the pulse integral (light yield). These preliminary results
are encouraging as to there is no strong cross talk in the SMT."""
2. RUN 91206 - LED/TDC - MuVAX2. ERP S/H card for counters 4E08-4E11 were
successfully replaced after several permutation and combination of small
tests for localising the problems.
3. RUN 91207 - LASER (Attico)
05-11-98 - 5T05(coincidence rate almost 10 times high) and 5T08(singles rate
very high) were taken out of the system after run 16641 to look at the PMT
and swap the PMT's between two modules to see whether the problems are with
the PMT's or with the grounding/placing of mylar etc. PMT's from 5T08 were
put in 5T05 and the tank mouth was covered as per check list. The rate has
gone down but 5T08 is still hot (10-11-98). PMT's from 5T05 were put into
5T08 and according to MO it is still flashing, so 5T08 is out of DAQ system.
Around noon on 05-11-98, the rate on 1C08 and 1W07 were found to be
abnormally high. The run 16641 finished in 32 minutes. Run stopped. muVAX1
and muVAX6 were taken out of the DAQ system and Global run was started with
other four muVAXs. It was found that the LeCroy HV system was malfunctioning
and was sending 4000V instead of 2000V to 1C08 and 1W07. LeCroy HV was
successfully changed. PMT's ON 1W07 looked fine. But on 1C08 after
the HV supply was changed the PMT's did not look good. May be both PMT's
are damaged. Needs more investigation. 1W07 is in DAQ system while 1C08 is
out of it.
Run 16644 started with full detector in the configuration. 5T08 & 1C08 are
out of the DAQ system.
Runs 16644-60 finished normally.
Run 16661 in was stopped because of power problem on rack 64. Details below.
Run 16662-65(JUNK) are very small and should be thrown out.
Run 16666-67 with muVAX 1 and 3 only. Good run.
Run 16668 in progress. Problems with muVAX2. Stopped to reboot muVAX2.
Run 16669(JUNK).
Run 16670 with muVAX 1 and 3 only. Good run.
Run 16671-72 finished normally.
Run 16673 stopped after 5.8 hrs for electrical maintenance. It is wednesday.
Run 16677 - with SM 3 to 6 only.
Run 16679-85 - Good global run.
As I has suspected, 5T05 is still very hot. The rate is atleast 10-12 times
higher than normal. On 06-11-98, BCC/IOK looked at 5T08-00,01. The tank is
out of DAQ system. Oil taken out and PMT's were looked at. PMT on side 00
has very high singles rate. Side 01 looks okay. HV of -1555V on side 00
and HV of -1440 on side 01. HV turned on without oil. 5T08-0 still out of
DAQ system. We are trying to see if the PMT calms dowm.
06-11-98: High singles rate observed on:
(*-high, **-more high, ***-veryhigh):
1T03-0(*), 1T11-0(*), 1T14-0(**), 1T16-0(*)
2E07-1(***), 2C14-0(***), 2B13-0(**), 2T14-0(**)
3T06-1(***), 3T07-1(***), 3T12-0(***), 3T13-0(***)
4C12-0(**), 4B14-0(**), 4T02-1(***), 4T04-0(*), 4T07-1(*),
4T10-0(*), 4T11-1(**), 4T12-1(***), 4T13-0(*), 4T15-0(***),
4T16-1(*), 4T17-0(***)
5B11-1(*), 5T01-0(*), 5T02-0(***), 5T02-1(***), 5T04-0(*),
5T05-0(***), 5T06-0(***), 5T07-1(**), 5T10-1(*), 5T11-0(*),
5T15-0(*), 5T16-0(**)
6B14-1(**), 6B13-0(*), 6T02-0(***), 6T07-0(***), 6t14-0(***)
As we see, on SM 4, 5 and 6 we have high singles rate on several top
counters. Reason not very well understood. Many of these tanks are being
investigated one by one.
07-11-98: Observation: The PMT 5T08-00 still looks very hot.
09-11-98: PMT on 5T08-00 was still very hot after 3 days. It has been
replaced but 5T08 still not in DAQ system.
10-11-97: Last night the security called Paulo Bernidini at about 11pm and
told that smoke has been seen coming from rack 64. Also smoke alarm was ON.
When Paulo came although he found everything in order, he switched off the
rack 64 and took out muVAX2 out of DAQ system. After some initial glitch
with starting the run, run 16665 was started with two muVAXes. On further
investigation, this morning it was found that the splitter box on rack 64
was damaged. It has been replaced and global run is going on.
10-11-98: 4B08 taken out of DAQ system. MO looked at the rates. Just put
back the things together and it looks fine.
muVAX2 problem fixed. No apparent problem for failure was understood. May
be some glitch. Run 16671 started with all the muVAXes. 4B08 and 5T08 are
fixed. They are in the DAQ system.
11-11-98 : High rate on 5T05 and 5T06. 5T06 - The PMT looks fine without
oil. With oil it is very noisy. Change the oil. Still it is
noisy. Do we understand it.
11-11-98 : NO CALIBRATION DONE BECAUSE OF ELECTRICAL MAINTENANCE.
12-11-98 : Power Glitch. Scare for a while but things turned out to be fine.
12-11-98 : Pulser Calibration finished for A1 vs A2.
13-11-98 : Pulser calibration in progress for A1 vs B1.
: 5T05 and 5T06 are back in DAQ system, JUST BEFORE RUN 16686.
TOHM rate on 5T05 is still very high. 5T05 is unplugged from
TOHM only due to very high rate.
Run 16686 going on normally.
Respectfully Submitted.
Brajesh Choudhary
CALTECH(MACRO-USA)
16-NOV-1998