H4/SPS Daily meetings
September 15
Status: We could only run part of the night, until about 4:00 AM. Beam expected at 8:30 PM 
. CAL calibration with 20 GeV pions completed.
Two configurations suggested by Leon tested as well (with 150 GeV pions).
Program: 10 GeV electrons (limited number of configurations). We will stop tomorrow at 7:00 AM. The area must be cleared by 8:00 AM.
September 14
Status: Program with 20 GeV protons completed (center of tower 2: 0,45,180 deg +1 position at 90 deg 100k events). Different configurations with 200 GeV electrons used for the FIFO full issue. As of today, we are in "democratc mode", so we have lost the capability to run at the highest energies (>250 GeV). To do list related to dismantling and shipping Configurations still to do
Program: 10 GeV electrons. Completion of the scan with 20 GeV pions.
Analysis: Dave Smith looked a little at position measurements in CAL single crystals, here. Benoit had a look at the 20 GeV pion run used for CAL calibrations. There is a very good agreement between the reconstructed energy of the MIP peak and that predicted by the MC, demonstrating that pedestals or light yields/gains have not significantly drifted over time.
September 11
Status: Smooth operation most of the time, except for 3 hours in the morning. Program of different geometrical configurations completed at 20 GeV. New configurations proposed by Philippe at different energies (200,100,50,20 GeV) to study the crack effects + direct contributions from the beam almost done.
Program: Different electronic configurations to investigate the FIFO full issue. Switch to 20 GeV (10 GeV?) protons.
Analysis: Luis presented the first comparison between MC and data for the ACD distributions. The agreement seems reasonable.
September 10
Status: Smooth operation most of the time. Program of different geometrical configurations completed at 50 GeV, well along at 20 GeV. Runs with different trigger engines (internal trigger for physical events: 1 range readout, 0-suppress, external trigger for random events: 4 range readout, non 0-suppress) performed successfully to study the pedestal drift issue.
Program: Completion of 20 GeV program. Dedicated runs near cracks at 200 GeV. Switch to protons+pions tomorrow morning, when the experts are around.
Analysis: Preliminary results of the "pedestal-drift" runs (Benoit). The expected effect is clearly visible, although this is still very qualitative.
September 9
Status: Smooth operation most of the time, but for a long interruption from 4:30 to 9 AM. Program of different geometrical configurations completed at 100 GeV. Specific configurations proposed by Leon (45 deg, with particles entering the tracker sideways within the thick-converter layers) were used as well.
Program: Specific studies for the "baseline restoration" (aka "pedestal drift") problem using LATTE's muti-engine capabilities (configuration files provided by Jim Panetta). CAL pedestals, internal trigger runs. Switch to 50 GeV.
Analysis: A look at the deposited-energy distributionsmeasured in the different CAL layers (Benoit): a factor close to 90%, dependent on the layer and the bombarding energy has to be applied to the data to get a good match with the data. It is not clear if this effect is only due to non-linearity in the extrapolation of the cosmic-muon calibration to the highest energy range. Philippe showed the dependence of the measured energy on the distance to the log edge. David P. has studied the beam width, found to be much narrower in the data than in the existing simulation runs. Jan and Niklas showed results on the FHE efficiency at 200 GeV. Since the deposited energy per layer is so high, there are only few events below threshold. The measurement must be repeated at lower energy.
September 8
Status: Smooth operation most of the time. Program of different geometrical configurations completed at 280 GeV. FHE tests completed at 280 GeV (theshold=0.5 GeV-2 GeV) at 2 different positions. Cerenkov counters have been checked (there was connection problems), and are now working, although the efficiency is low.
Program: Specific studies for the "baseline restoration" (aka "pedestal drift") problem (waiting for Ric's help to implement muti-engine capabilities). CAL pedestals, internal trigger runs. Switch to 100 GeV.
September 7
Status: The beam is now much more stable. Calorimeter calibration completed, ACD calibration completed, scanning of 200 GeV configurations almost completed. Some runs were repeated after it was found that 4 scintillators used for the beam tuning were still in and be moved out. The pressure in the 2 Cerenkovs (1.2 bars
so far) was set to 0. The dependence of the calorimeter measured energy as a function of rate has been investigated ("baseline restoration" problem). The effect is clearly visible. We decide to limit the rate to 400 Hz for the rest of the run. The time of the daily meeting will be moved to 5 PM to enable people on the previous night shift to attend.
Program: switch to 280 GeV and repeat the same configurations. Specific BT configuration files will be prepared by Luca and Carmelo to study the FHE efficiency using the SPS timing settings. As proposed by Anders, the TEM diagnostics will be on by default (BT 6 which is now the baseline).
Analysis: the first quick comparison with the MC simulations at 100 GeV shows a reasonable agreement for the tracker hit multiplicity (the multiplicity is larger for the data) and the energy deposited per layer in the calorimeter. No comparison is available for the ACD yet. More simulations are needed.
September 6
Status: First day of beam. We were supposed to have the beam at midnight, we got it at 3PM. The timing was looked at, the calorimeter signal is now coming earlier with respect to the tracker as compared to PS. BT 5 configutation with cal/tkr in the middle of the trigger window at SPS is now the baseline.The calibration of the calorimeter (cross pattern) at 100 GeV was started then interrupted to let the experts optimize the beam tuning at the highest energies. Many interruptions due to machine problems. Benoit attended the weekly users' meeting (moved from Thursadt to Wednesday as tomorrow is a holiday in Switzerland): there will be machine development (no beam) from next Tuesday 8 AM to Wednesday 4 PM. A threat on our running with the "0 mrd" configuration (allowing us to get the highest rate at high energy) was mentioned during the meeting, as the H2 users (sharing the same target) would like a less detrimental configuration for them. Finally, a way around was found and we wil keep this configuration at least until Monday.
Program: completion of the 100 GeV calibration runs, ACD calibration with protrons+pions, switch to 200 GeV, scanning of different (X,Y, theta) configurations
T9/PS run Daily Briefings - 3PM
Daily briefing minutes
August 21 - 13-3-005
Communications |
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Online&DAQ Report | -Interruption today between 8:30 and 17:00 because of an intervention on a magnet in the PS hall. The program on positrons and electrons at 1 GeV is essentially complete (~ 900 K for both). Alessandro has moved the second arm of the tagger at larger angle in order to get lower energy gamma-rays. . |
OfflineReport | The pipeline at SLAC is back up and there is no backlog left. Mizuno shows some simulation results concerning positron annihilation. With the current "annihilator", the probability for annihilation at 1 GeV is 1e-3. The probability for having two gamma rays with energy greater than 30 MeV is about half as low, 0.5e-4. Half of these events are actually contaminated by a bremstrahlung gamma-ray. The angle between the gamma-ray directions can help distinguish between contaminated/ pure annihilation events, the latter being associated with greater angles. |
Program | We will resume data taking with the tagger at .5 GeV when the beam is back, using different configurations, until tomorrow morning. We will then proceed with "special configuration" runs, namely using different FHE thresholds with 5 GeV electrons. |
Notes |
August 20 - 32-1-A24
Communications |
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Online&DAQ Report | -Interruption today between 10:30 and 12:00 because of an local power outage (Benoit accidentally pushed the emergency bottom in on of the barracks while trying to pull an ethernet cable). We couldn't switch the power back on by ourselves, after proper authorization of the control room. The expert on call had to drive over. Everything went back up without too much problem. Otherwise smooth operation. |
OfflineReport | The pipeline at SLAC has been stuck for more than 12 hours because u23 is full. We are eagerly waiting for California to wake up. |
Program | We took advantage of the interruption to prepare for the positron run. The annihilator is now a piece of 27-mm thick plexiglas. The two finger detectors are now side by side. We will start running positrons around 4 PM tonight and keep running overnight. |
Notes |
T9/PS run Daily Briefings - 3PM
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August 19 - 32-1-A24
Communications | - large increase in the beam rate for standard setting last night when running photons, had to reduce rate by closing slits to 51 to get usual rate on S0 (20K/cycle) and reduce pile-up; please monitor this number when taking photons and act on slits if needed |
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OfflineReport | - Benoit on CAL pedestal drift: analysed rate effect in CAL crystal on pedestal for p runs; there is a clear effect that shows a broadening of the landau peak in CalEneSum at high rate; cutting on GemDeltaEvtTime and selecting particles at the beginning of the spill the Landau appear normal. The same is confirmed when analyzing few runs taken with lower p rate. Positron and electron runs seem unaffected. Michael looking at tkr data to seek for any rate effect; the idea is to monitor the efficiency of a FE vs GemDeltaEvtTIme, as no runs with different rates are available for p through the tkr. |
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Communications | - Magnet failure: MNP17 colling system failure at 1AM stopped data taking for several hours but no damage on hardware. Physics restarted after 2 hours w/o silicon tagger for CAL calibrations. Magnet repaired in the morning |
Online Report | - DAQ sync studies going on |
Offline Report | Francesco: |
Program | - Complete DAQ sync studies |
Notes | - Fill elogbook |