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

- Transmission Experiment -

(old version up to May 2016)

DAQ preparations:

To run neutron time of flight measurement you first have to do some preparations:

    trigger matching
1. Switch on the electronics:  
  switch on
VME/NIM mixed crate in rack 1
Acc.Ref.Signal in rack 3
(see here)
2a. Start MBS:  
  login to RIO4-1: telnet rio4-1
user name: ntofdaq
password: ***********
  go to working directory cd mbsrun/ntot
  start MBS prompter mbs
  initialise MBS @start
2b. Start Scaler readout Program (shm2file)  
  login to RIO4-1: telnet rio4-1
user name: ntofdaq
password: ***********
  go to working directory cd mbsrun/ntot
  start shm2file ./shm2file
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. 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
5. 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: rio4-1
or Start Go4: (not for continuous storage mode)
 
  login to MARGE ssh -XC ntofdaq@marge
password: ***********
  go to working directory cd $GO4WORKDIR/ntot
  start Go4 go4 ntot.hotstart &
6. 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 &
7. Switch on the detectors:  
  login to FWK055 (HV control PC) rdesktop -g 1240x900 -a 16 -k de fwk055
user name: ntofdaq
password: **********
  switch on the detectors you want to use (cf. cabeling scheme) start "isegCANHVControl" via desktop shortcut
8. Start RFIO server and client:  
  login to ZIRKONIA ssh -X ntofdaq@zirkonia
password: ***********
  go to directory for list mode data files  cd /hdd2/ntofdaq/lmd/ 
  start RFIO dispatcher  rawDispRFIO 
  In MBS:
connect to RFIO Server

connect rfio zirkonia -disk
9. Open MBS monitoring windwos for ELBE Operators:  
  login to fwkdaq1 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. open list mode file open file size=900 -auto -rfio
if it is the first file enter:
open file /hdd2/ntofdaq/lmd/filename_.lmd first=1 size=900 -auto -rfio
 
  • note down name of first file
3. start acquisition sta acq
 
  • note down start time
4. wait ...
5. stop acquisition stop acq
 
  • Attention: Never stop acquisition, when the absorber is moving! -> check MBS output
  • note down stop time and live and dead time given at the end of mbsprint.l
6. close list mode file close file
 
  • note down name of last file

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
  • goto measurement hut 250 and switch of VME/NIM mixed crate (left crate, upper most crate) (see here)
  • wait shortly and switch them on again
  • perform points 2. and the last step of point 8.
  • LEA message:
    ": 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
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 prompter 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