Low-Energy Muon (LEM) Experiment  0.5.0
Quick Howto
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  • Stopping and Restarting Midas clients
    • Do not restart vme_fe, nemu_analyzer and mlogger, if a run is active!!!
    • Use the Programs button on the Midas status web page on http://lem00/.
    • If the shut down of a Midas client fails, you may try it once more. If this still does not work you have to kill the client manually, followed by an ODB cleanup:
      [nemu@lem00]$ killall -9 <client_name>
      [nemu@lem00]$ odbedit -e nemu -c "cleanup"
    • use the Programs button on http://lem00 to restart the client
  • Shutdown or Recovery of Midas
    • Stop run, if run active before shutting down Midas!!!
    • If stop run does not work from Web browser, try
      [nemu@lem00]$ odbedit -e nemu -c "stop"
    • If this fails, bad luck. Shutdown Midas with
      [nemu@lem00]$ nemu_mcleanup
    • if shutdown was succesful without ODB corruption the system can be re-started as described above
    • if ODB is corrupted, goto Recovery of Midas.
  • Run control on pc12438, pc12439
    • use Firefox as web browser, control experiment through http://lem00/?exp=nemu.
    • enter in a terminal/console beamline to start muE4 beam line control
    • enter in a terminal/console hvEdit -e nemu -h lem00 to start HV control,
      or use the desktop icon
    • other GUI's similarly.
  • How to change event definitions
    • goto http://lem00/Equipment/Trigger/Settings?exp=nemu
    • Do not change the settings (unless you know what you do) for T0_Offset TDC_Disable_AtStartup TOF_BC_Window TOF_BC_PileUp_Window
    • goto http://lem00/Equipment/Trigger/Settings/Events?exp=nemu subdirectory to enable/disable different Event types:
      • Event0: BC-MCP1-MCP1_e+
      • Event1: BC-TD-MCP2-LE_e+
      • Event2: BC-TD-LE_e+
    • for LE-muSR, disable Event0 and Event1, enable Event2
    • To change settings for Event1, for example, goto http://lem00/Equipment/Trigger/Settings/Event_1_Settings?exp=nemu
      • you have the choice to enable/disable TD, MCP2, BC or e+.
      • you have the choice to set TD or MCP2 as "master" detector, i.e. times are measured with respect to the "master"
      • you may change the data window (66560 TDC channels correspont to 13musec) and the TD-MCP2 TOF window (TOF_M2_Window). TOF_M2_Pileup_Window is not yet implemented in the vme frontend
      • don't change master_delay and positron_delay unless you know what you do
  • Vme statistics
  • Online analysis on pc12438, pc12439
    • Login as nemu on either pc12438 or pc12439.
    • /mnt/home/nemu and /mnt/data/nemu will be automatically mounted.
      They point to
      lem00:/home/nemu and lem00:/data/nemu.
      This makes data on lem00 available on pc12438, pc12439.
    • enter any2many for file conversion, if necessary (musrfit does not need file conversion)
    • run musrfit as usual, input files on /mnt/home/nemu/analysis/YYYY
    • use roody to inspect the online root histograms directly


  • VME system:
    • 2 VME crates
    • CAEN TDC 1190B, 64 channels, 195.3125 ps (1/160MHz/32) LSB
    • 2 SIS3820 scaler, 32 channels each
    • 5 PSI CFD950, 8 channels each, CFD programmable through mscb
    • 5 PSI SP950, 8 channels each, splitter with one input and two outputs per channel
    • SIS3100/1100 VME-PCI interface with optical link
  • VME addresses
    • TDC 1190B: 0xEE000000
    • 1st SIS 3820: 0x38000000
    • 2nd SIS 3820: 0x39000000
    • CFD950:
      • 0xC2000000 (the rightmost module, ch 0-7)
      • 0xC2010000 (ch 8-15)
      • 0xC2020000 (ch 16-23)
      • 0xC2030000 (ch 24-31)
      • 0xC2040000 (ch 32-39) in the 2nd VME crate)
      • see http://lem00:8000/DetectorElectronics/13 for programming CFD using MSCB
  • RHEL 7 lem00 (IP XXX.XXX.140.28) as backend (pc8582 without RAID as backup system)
  • RHEL pc12438, pc12439 for run control, online analysis
  • psts03/05 terminal server to connect RS232 devices to slow control system
  • mscb006 submaster to connect SCS2001M slow control system
  • mscb008 submaster, HVR400
  • mscb009 submaster, HV-APD
  • mscb023 submaster, FUG-SpinRot
  • mscb034 submaster, FUG
  • lemplug on http://lem00
    • LS_Sample
    • LS_Mod_LS336
    • NN3
    • HV_FUG
    • HV_SpinRot
    • MSCB009
    • Laser
    • PSTS03
    • ACP28
    • SCS2001M
    • K2400
    • APR260
    • NN13
    • MSCB006
    • MSCB008
    • PSTS05
  • hipa-mue4, separate beamline control PC in LEM counting room
  • mpc1231, the separator Sep61 control PC
  • XXX.XXX.140.141 PSTS03
  • XXX.XXX.140.19 PSTS05
  • XXX.XXX.140.18 lemplug
  • XXX.XXX.140.44 lemplug2
  • XXX.XXX.140.39 LEM vacuum system control, port 2000
  • XXX.XXX.140.45 Sep61 vacuum system control, port 2000
  • XXX.XXX.140.46 PS64 vauum system control, port 2000
  • XXX.XXX.140.47 lem-lm510 LHe level meter
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