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 July 2013)

DAQ preparations:

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

trigger matching continuous storage
1. Switch on the electronics:
switch on
VME/NIM mixed crate in rack 1
Acc.Ref.Signal in rack 3
(see here)
2. Start MBS:
login to RIO42: telnet rio42
user name: ntofdaq
password: ***********
go to working directory cd mbsrun/ntot
cd mbsrun/ntot_cont
start MBS prompter mbs
initialise MBS @start
3. Set MBS initialisation parameters:
login to ZIRKONIA (in another terminal window) ssh -X ntofdaq@zirkonia
password: ***********
go to working directory cd mbsrun/ntot cd mbsrun/ntot_cont
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 ZIRKONIA (in another terminal window) ssh -X ntofdaq@zirkonia
password: ***********
go to working directory cd mbsrun/ntot cd mbsrun/ntot_cont
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 cd lea/ntot_cont_online
start LEA lea -pro ntot -men
choose right settings Source: MBS samples
Input file/node: rio42
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 cd lea/ntot_cont_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 FWK21 (HV control PC) rdesktop -g 1240x900 -a 16 -k de fwk21
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 ZIRKONIA from any Windows PC using putty
(usually in "Start"->"Programme"->"PUTTY"; if not installed get it from "S:\Putty")
putty
Host Name: zirkonia (leave all other values default)
login as: ntofdaq
password: ***********
go to working directory cd mbsrun/ntot cd mbsrun/ntot_cont
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
  • RIO freezes or shuts down
  • goto measurement hut 250 and switch of VME/NIM mixed crates (see here)
  • wait shortly and switch them on again
  • perform points 2. and the last step of point 8.
  • 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
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 Partzsch

Contact

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