Contact

Dr. Roland Beyer
PostDoc / Beamline scientist
Nuclear Physics
roland.beyerAthzdr.de
Phone: +49 351 260 - 3281

Data Acquisition Manual: How to run Neutron Time of Flight Measurements at nELBE

- Monitor DAQ -

The beam stability is monitored using one of the scanner detectors (cf. nELBE Beam Scanner). The count rate of this monitor detector is also used by the ELBE operators for beam tuning.

DAQ preparations:

To run the monitor DAQ you have to do some preparations:

     
1. Switch on the electronics:  
  switch on
VME/NIM mixed crate in rack 1
Acc.Ref.Signal in rack 3
see here
  connect the signal cables of ScannerH (cf. cabeling scheme) to the inputs of the "2fold Multi-Box" see here
2. Start MBS:  
  login to RIO4-0: telnet rio4-0
user name: ntofdaq
password: ***********
  go to working directory cd mbsrun/ntot
  start MBS prompter mbs
  initialise MBS @start
3. Set MBS initialisation parameters:  
  login to FWKDAQ1 (in another terminal window) ssh -X ntofdaq@fwkdaq1
password: ***********
  go to working directory cd mbsrun/ntot
  open setup.ini for text editing
if you want to do some special settings
xemacs setup.ini &
  or open setup_short.ini for text editing
if you only want to change only the important special settings
xemacs setup_short.ini &
4. Start scaler readout program
 
  login to RIO4-0 (in another terminal window) telnet rio4-0
user name: ntofdaq
password: ***********
  go to working directory cd mbsrun/ntot
  start "shared memory to file" task ./shm2file
5. Open MBS monitoring windows:  
  login to FWKDAQ1 (in another terminal window) ssh -X ntofdaq@fwkdaq1
password: ***********
  go to working directory cd mbsrun/ntot
  open mbslog.l, mbsprint.l and mbs_ratios.l for monitoring
(each in its own terminal window)
tail -f mbslog.l
tail -f mbsprint.l
tail -f mbs_ratios.l
tail -f mbs_scaler.l
6. Start LEA:  
  login to ZIRKONIA ssh -X ntofdaq@zirkonia
password: ***********
  initialize system variables source .profile
  go to working directory cd lea/ntot_online
  start LEA lea -pro ntot -men
  choose right settings Source: MBS samples
Input file/node: rio4-0
or Start Go4:
 
  login to MARGE ssh -XC ntofdaq@marge
password: ***********
  go to working directory cd $GO4WORKDIR/ntot
  start Go4 go4 ntot.hotstart &
7. Set LEA initialisation parameters: (if LEA is used)
 
  login to ZIRKONIA (in another terminal window) ssh -X ntofdaq@zirkonia
password: ***********
  go to working directory cd lea/ntot_online
  open setup.ini for text editing if you want to do some special settings xemacs setup.ini &
8. Open histograms to monitor (create - select histogram -> plot)
  detector rate RATE -> Index 3
  time difference PMT2-PMT1 TDCDIFF2
  time of flight in (0.9766 ns/ch) TDCSUM2
9. Switch on the detectors:  
  login to FWK055 (HV control PC) rdesktop -z -x 0x80 -g 1600x1000 -a 32 -k de fwk055
user name: ntofdaq
password: **********
  switch on ScannerH (cf. cabeling scheme) start "isegCANHVControl" via desktop shortcut
10. Open MBS monitoring window for ELBE Operators:  
  login to ZIRKONIA from any Windows PC using putty
(usually in "Start"->"Programme"->"PUTTY"; if not installed get it from "S:\Putty")
putty
Host Name: fwkdaq1 (leave all other values default)
login as: ntofdaq
password: ***********
  go to working directory cd mbsrun/ntot
  open mbs_ratios.l for monitoring tail -f mbs_ratios.l

Running the DAQ:

Now the measurement can be started. This has to be done in the MBS prompter (prm):

  in LEA
1. start LEA analysis click Analyze events
  in MBS
2. start acquisition sta acq
3. wait ...
4. stop acquisition stop acq

If any problem occurs:

Problem Solution
  • DAQ crashes
    • repeating popup message in NX window: "Bell in session Shell"
    • repeating error message: "... found trigger type = 0, read again trigger status ..."
  • stop acq
  • @stop
  • exit (if it does n't work: CTRL + C)
  • resl (2x)
  • mbs
  • @start
  • if there is a message saying something about zombies (repeat maybe several times):
    • stop task -zombie
    • @stop
    • exit
    • resl (2x)
    • mbs
    • @start
  • sta acq
  • RIO disconnects
    • message "connection closed by foreign host" in MBS terminal window
  • reconnect to RIO (Setup step 2.) without "@start"
    • if mbs is still running, no MBS messages will appear (i.e. connection to RIO was lost)
      • stop measurement regularly ("stop acq" and "close file")
      • run procedure for error "DAQ crashes" (see above)
    • if mbs is not running, usual MBS messages will appear (i.e. RIO rebooted)
      • @start
      • sta acq
  • restart scaler readout program (Setup step 4.)
  • RIO freezes or shuts down
  • switch of VME/NIM mixed crates (see here)
    • by going to measurement hut 250 or
    • by using network controled power socket (see here)
  • wait shortly and switch iton again
  • perform setup step 2. and 4. to restart
   
  • LEA message:
    "<ERROR>: Value out of bounds of TRGTIME ..."
  • can be ignored
  • iseg HV Control shows current trip for one or more detectors
If Vmeas is stable:
  • use button 3 "Status3 software current trip" to reset status and
  • CTRL+m to reset "emergency off"
If Vmeas is not stable:
  • Switch the channel off until the source for the high count rate is eliminated (e.g. while beam tuning)
If Vmeas remains unstable:
  • Replace the HV divider of the PMT
If Vmeas remains unstable:
  • Replace the PMT
  • DAQ is frozen
1. leave MBS CTRL+C
2. reset RIO resl (2x)
4. restart MBS prompter mbs
  • any other problem related to data acquisition, electronics or detectors
  • call Roland Beyer
  • any other problem related to Pb loop operation
  • call Arnd Junghans or Maik Görler

Contact

Dr. Roland Beyer
PostDoc / Beamline scientist
Nuclear Physics
roland.beyerAthzdr.de
Phone: +49 351 260 - 3281