Minutes of the Meeting of the Technical Board ============================================= August 29th 2001, 9:30 - 12:45 The meeting was chaired by Klaus Ehret. He pointed out that the focus of this meeting will change now from pure technical detector and installation issues more into a commissioning meeting. Access to Detector (J. Spengler): --------------------------------- The dates of the regular access days as well as the corresponding schedules can be found (as usual) on the Web-page called "Run coordination". In order to make efficient use of possible short accesses to our experiment, J. Spengler asked all the groups to send the name(s) of interested contact persons. He will ask Hera to inform him about possibilities to enter our area via ZZ (zeitweiser Zugang = controlled access) and then inform the above-mentioned contact persons. Radiation Protection (R. Wurth): -------------------------------- Rainer informed about a change in the "German Regulations for Radiation Protection". The most important modification for us is the reduction of the limit for the so called "controlled area" from 15 mSv/year to 6 mSv/year. As a consequence, not only the 3rd floor of the trailer and the area below the trailer are controlled areas but that the 2nd floor of the trailer and rooms 201 and 301 are added. In addition, those people working for more than 4 h/week in one of these place have to ask a neutron-dosimeter. All people have want to work in one of these places are asked to contact Rainer who will inform you about all the relevant details. After that, Uschi will organize the dosimeters as usual. Please make sure that you have your dosimeters with you when working in one of these places. For comparison, you should have in mind that the natural annual exposure in northern part of Germany is 1-2 mSv. Run Coordination (K. Ehret): ---------------------------- Klaus introduced the members of the run team and explained their duties which include: coordination of daily running, chairing the meetings (with minutes), defining (with management) the run strategy, communication with Hera. Due to our limited manpower they have to acquire a high level of understanding in running our experiment in order to reduce the load on our DAQ group. The steps to recommission our experiment were sketched (dry run, occasional beam operation with target and VDS pots, switch on detector to collect minimum bias data for calibration and alignment, commission pretriggers, SLT and afterwards FLT. Vertex (K.T. Knoepfle): ----------------------- The VDS system is working and waiting for re-commissioning with beam. 49 Helix wafers have been delivered, 15 of which were given to the ITR group. Answers to Klaus questionnaire: VDS is ready for 'dry run', manpower has been allocated. As soon as stable target operation is established, the pot insertion will be exercised (look for output of the rf-antenna). This requires 2 hours if everything is ok. Later on, sparsified and unsparsified data are recorded to test and improve the Helix read-out. For alignment purposes at least 100k events are required. Including analysis, this will take about 1.5 months. During the re-comm. phase, no man-power problems are expected. However, problems might develop during the next year. Inner Tracker (C. Krauss): ------------------------- Hardware status: All chambers are installed except MS10- (next access day), MS05 (now ready), MS06 (waiting for MC6 installation) and MS14, 15 (production on schedule, installation planned for X-mas break). The operation of the gas system has been made easier by a graphical user interface provided by a summer student. Therefore the operation can be handed over to our three gas technicians before start of running. B. Schmidt mentioned that these technicians are no longer supposed to work just for the outer tracker. They will operate ITR, OTR, Muon and Rich systems. This implies that the the corresponding groups provide the expertise in case of non-standard situations which cannot be handled by our technicians. All auxiliary systems are in good shape with some tests (water cooling) and repair work (optical fibers) still pending. Run preparation: All necessary steps are taken (or will be taken next week) for the dry run. The group has no interest in occasional beam because they need constant beam operation to start the chamber training. They need about 4-5 weeks of stable (= 50% up-time) Hera operation with target rates between 4-10 MHz. Carsten made clear that the chamber training requires these interaction rates. Reliable numbers on efficiency and alignment will not be available before end of February. This statement provoked quite some discussion. Carsten explained that most of the chambers have been disentangled during the shut-down and that all chamber were exposed to air over months. Thus the chambers have to be treated like new chambers. The training process takes several weeks depending on the availability of beam-time and on the behavior of the chambers themselves. Outer Tracker (H. Kapitza): --------------------------- The big gas leak in TC2- was found and fixed during the previous access day. The leak rate of the total gas system is now about 100 l/h which corresponds to 0,5 %/h. The installation of the still missing magnet chambers MC6 and MC8- is planned for September 24th. The ASD-8 tests for MC8 and MC3- remain to be done which is planned for the October break. They hope to complete the TLB installation by October as well. However, debugging the TLB-TFU links will take till end of this year. Run preparation: Herbert expressed interest in all stable conditions lasting for at least 6 h with 12 h prewarning. They need some "no beam" time for undisturbed HV tests as well as stable proton beam for threshold optimization. Target runs at 5 MHz with about 500 k minimum bias data are required for debugging, masking and CnA. After these steps a HV scan (12 h beam-time) in order to determine the efficiency plateau is planned. Thereafter the calibration has to be redone at this new working point which is planned to be available by Jan 2002. ECAL pretrigger (M. Bruschi): ----------------------------- Marco reported that the commissioning of the ECAL electronics is still not finished. 195 (226 in total) read-out boards and 114 (128) pretrigger boards have been commissioned up to know. About 40 bad read-out boards were identified which were found to CAEN for repair. The firmware of the pretrigger boards was upgraded and the brems-recovery procedure was tested. The instabilities in the Sharc transmission were solved. The noise situation could be improved compared to last year. This was documented by several plots showing the width of the pedestal distributions for the three different ECAL sections without and with HV. Innermost section: without HV = 1.9 ADC channels, with HV = 1.9 Inner section with preamps: without HV = 0.7 ADC channels, with HV = 1.3 Middle section: without HV = 0.7 ADC channels, with HV = 0.7 Outer section: without HV = 0.7 ADC channels, with HV = 0.7 A detailed transmission test yielded 4 errors in 84k events. Two boards producing these errors were localized. MUON (M. Titov): ---------------- Maxim was not able to give a detailed report because he just came back from Moscow. The noise situation of the Muon system did not change during the last weeks. The complete read-out is working except one pixel crate. A replacement for the stolen PC (steering of gas system) was reinstalled and the gas system will be restarted soon. MUON pretrigger and RICH veto (M. Boecker): ------------------------------------------- According to Matthias, all the hardware of the pretrigger system including pixel pretrigger was reinstalled. The to-do list comprises the completion of the pixel pretrigger (LUTs, masking and monitoring), connection tests and improvement of data quality monitoring. The RICH multiplicity veto includes 112 base sum cards (8/FED crate), 14 FED sum cards (1/FED crate), 1 veto card and one veto distribution card. The first BSCs to equip one FED crate are available, the FED sum cards are produced and equipped, the layout of the veto card will be finished soon. The October access will be used to install the available electronics. RICH (M. Staric): ----------------- Marko reported that minor repairs and tests of the photon detector were finished by end of June. The most outstanding problem is still (since months) the missing gas expert. It is expected that routine operation of the gas system can be handled by the gas technicians, but the filling procedure is known to be rather difficult. Despite a lively discussion this problem could not be solved during the meeting. The run preparation seems to be in good shape. However, the manpower to operate the Rich seems to be very limited and we cannot expect experts to be around a Desy for the whole year. Inner high-pt (R. Mizuk): ------------------------- The shielding of station 1 was completed during the last days which means that no more hardware activities within the magnet are planned. The HV training with nitrogen is going on and daily checks underline that the noise level is better compared to last years situation (threshold of 0.7 - 0.8 V compared to 1 V in 2000). The system is ready for a "dry run" and waiting for target operation to check occupancies and take data for alignment and efficiency measurements. Outer high-pt ( ): ------------------ TRD (): ------- Target (K. Ehret): ------------------ Concerning the target hardware, everything is basically ready and they are waiting for Hera. Some software items like slow control integration, online monitoring and switching over to the final DB server still have to be finalized. Data Aquisition (V. Rybnikov): ------------------------------ Vladimir mentioned recent DAQ activities like upgrading the FCS library, working on the data quality histogram viewer and re-configuring data bases needed for run and slow control. Most subsystems started to get some experience with the new DAQ configuration running in stand-alone mode or via the switch. Up to now, no obstacles were found. Some slow control processes like OTR_gas, SVD_possrv require some work by the subgroups to make them running. The DAQ group plans to be ready for the "dry runs" planned for mid of September. First Level Trigger (M. Noerenberg): ------------------------------------ Michael reported on a detailed comparison of the FLT hardware (OTR TFUs, Muon tubes and pixel) with the FLT simulation using 5, 10 and 20 MHz minimum bias data (the famous test vector test). The 5 and 10 MHz data have been analyzed and all details are understood; the 20 MHz data are still being analyzed. It is planned to include TDU and TPU in the analysis. In order to reduce the latency when triggering on muons, it was studied whether MU4 can be omitted from the trigger (gain in latency = 450 ns). The width of the residual distribution in MU1 increases from 1.3 cm to 2.2 cm. However, the influence on the trigger rate is not known up to now. After this study the pt-dependence of the geometrical J/Psi efficiency for different trigger conditions was shown. For a pt-cut of 1 Gev/c, the numbers are as follows: OTR+Muon: 1 track=72%, 2 tracks=21%, ITR+OT +Muon+pixels: 1 track=95%, 2 tracks=57%. One FLT-track in OTR and and 2 SLT-tracks in ITR+OTR=47%. The commissioning plans include: continue the test vector test, prepare software to test the optical links. The time schedule is tight due to the limited manpower. Nevertheless they hope to run the FLT in "spy mode" begin of November. Second Level Trigger (L. Soezuer, P. Kreuzer): ---------------------------------------------- Lars announced that the SLT simulation package has been added to Arte. Some minor modifications still have to be done. Documentation will be made available on the SLT-page. The Muon SLT code reads the pretrigger information, calculates a region of interest and looks for hits. The MC simulation of this code has to be extended to the pixel chambers. Several open questions are still left like whether the wires of MU3/MU4 should be used or whether the code should look for tracks also in the y-view? Peter answered the questions of Klaus questionnaire. They plan to cycle the new SALT code during the "dry run" in October. The new ITR sparsification has to be tested. The final goal is to collect J/Psi samples for offline analysis by end of Feb 2002. Fourth Level Trigger (J. Hernandez): ------------------------------------ Jose reported that both online computing and L4 farm have been commissioned already now. L4 PCs are now connected to the Can bus, all machines received an upgrade of the Linux OS and online running is now possible without AFS. A maximal logging rate of 12 MB/s was measured, whereas the archiving rate is 5 - 10 MB/s. Improvements are possible. During the last weeks some effort was spent to allow for Monte Carlo production (event generation + detector simulation) on L4 farm. The corresponding processes can be started by "Run control", the data are written to disk and archived in the usual way. J. Spengler September 5th, 2001