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4th Workshop on ALICE Installation and Commissioning


									              4th Workshop on ALICE Installation
                     and Commissioning
                                  January 16th & 17th , CERN

                                 Muon Tracking
                                    (MUON_TRK, MCH, MTRK)

                    Conclusion of the first ALICE COSMIC run in December 2007.
              Status of Hardware during Run

             Dimuon Forward Spectrometer (DFS) Tracking Chambers :
                     5 stations, each station has 2 detection planes or chambers
                     1 chamber/plane gives an (x,y) coordinates


                                                         3                         μ-
                                                                 4    5
         Station 1
              Station 2
                                 read out during the december cosmic run.
              Status of Hardware during Run

            Dimuon Forward Spectrometer (DFS) Tracking Chambers :
                    5 stations, each station has 2 detection planes or chambers
                    1 chamber/plane gives an (x,y) coordinates

            During the december cosmic run :
                     almost everything is installed (but local commissioning is not finished yet)
                     1/5 of the DFS was powered
                          • Full Station 1 most of the time
                          • part of Station 1 + part of Station 2 for the “2 LDC in global” test
                     no particular issues
                          • air cooling (St1 and St2 is very stable), temperatures look fine
                          • power ok (a few trips have been seen on HV and LV)
                          • our last day (Tuesday 18th) was perfectly stable !

            No real DAQ issues :
                     compliance with DAQ global achieved
                     really stable

            Readout times (in 0-suppressed mode after taking pedestal runs, threshold
            calculation with a DA included in our rpm, etc… = conditions of real data taking ):
                      Trigger 4 kHz Busy 307 us Readout rate 2050
                      Trigger 40 kHz Busy 485 us Readout rate 2050
                      Trigger 400 kHz Busy 496 us Readout rate 2050
                      Trigger 4 MHz Busy 497 us Readout rate 2050
                      Trigger 40 MHz Busy 497 us Readout rate 2050

            Readout rate is slower than expected (lab measurements gave busy ~ 220 μs) :
            looking for possible explanation
                      → saturating the buffer slows down the readout (algorithm scan through a
                      lot of events in the DSP memory)
                      in normal data taking mode, an “open” muon trigger (no pT cut) will not be
                      greater than 5KHz.

            DCS in very good shape :
                     final state machine for low & high voltage works
                     temperatures, gas flow is monitored
            ECS :
                     scripts are ready (close to final) and working (tested during run)
                     automatic generation of command depending on which DDL/equipId are
                     declared in DATE

            Connection DCS-ECS (?) is not done yet

            Trigger :
                          first days have been painful… but it finally worked
                          we played at “you’re busy; not we’re not ; yes you are ; etc…” along with
                          trigger people and other subsystem ;-)

            HLT :
                          some global run were taken with HLT ; is it ok ?
                      Online Monitoring/Offline

            Online Monitoring :
                    MOOD for muon_trk is in very good shape
                              pedestal and gains visualization
                              some global histograms (pad occupancy, hit map, errors)
                    Data from gdc have been monitored during run in global and …

  That’s clearly a hit
                      Online Monitoring/Offline

            Data Storage :
                     data are on CASTOR and some ESD are produced

            Data Quality Checks :
                    Is it about QA histograms…?
               COSMIC Data, Analysis Results

            Raw data quality, event displays,
            Calibration results, Alignment results,
            Data reconstruction (ESD)
            Data analysis, First performance estimates i.e. signal/noise, tracks etc.

            All this is ongoing, but no results so far…
                        calibration runs have been taken
                        pedestal runs show nominal/expected noise
                        gms doesn’t seem to increase noise when running
                        ESD are not analyzed yet ; we will probably reconstruct a few clusters
                        (give an idea on clusters size, charge and S/N )
                    Hardware/Software Status for
                        February Run + Goals
            February Run :
                     Full station 1 (as in december)
                     Full station 2 (1/4 was successfully included in global in december)
                     1 DDL from station either 3, 4 or 5

            Goals :
                          Pedestal/noise : done with the DA (committed in AliRoot)
                          calibration : done
                          running with 0-suppression : done
                          alignment and tracks : needs tracks ! (and all the stations + survey)

            Mostly the february run will be useful for testing the stability and training people.
            Some software work is needed as well to test and to finalize pieces of software
            (calibration, ECS scripts).
                                 Action to Completion
          Station 1 : ready for beam (dead channels ? but <<1%, all HV ok)
          Station 2 : ready for beam (to be confirmed this week)
          Station 3 : finishing the local commissioning
                                                            can not be stopped during the 5 weeks
          Station 4 : finishing the local commissioning
                                                            of the feb. cosmic run !
          Station 5 : finishing the local commissioning
          • Very good behavior of St1 : Cathode Pad Chambers works ;-)
          • Readout (CROCUS) is compliant with DATE and Trigger patterns handling is fine
          (L1/2 reject are implemented and tested in lab)
                     1 LDC fully loaded ok
                     and going to 2 LDC (partially loaded) was straightforward
                     → including more should not be a problem (parallel treatment)
          • software for data taking (DA, ECS scripts, MOOD) is in very good shape
          • offline is working on the data ; pedestals runs are in OCDB and look fine

             Visualization of a pedestal run
             in the OCDB.
                                 Muon_trk questions

          •Standalone runs with CTP emulator : will it possible to have an “all.seq” that include
          an sod+l2a+eod ? (without loading the 3 seq)

          •What about documentation for shifters : ACR machines are disconnected from
          outside world. Everything should be done locally…
               • ksnapshot + “openoffice, or anything else convenient”

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