Contact

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

Data Analysis with LEA (up to April 2010)

(latest version)

The data stream or the list-mode data files written by MBS can easily be analysed using the GSI program LEA. LEA can directly read the GOOSY file format used by MBS.

The LEA project for the whole can be found at the PC fwk28 in the following directorie:

fwk28:/home/ntofdaq/lea/nng

This directorie contains the file f_anal_nng.c, which is used to define the data analysis procedures depending on the users wishes. Every change in this file, written in the programming language C, has to be accepted to the total LEA project by running the "make" command.

One can include every standard C command to the f_anal file to manipulate the data. To accumulate histograms, one has to use the commands HISACC1I(1DHIST,X,VALUE) and HISACC2I(2DHIST,X,Y,VALUE). These commands will increase the content of channel X of a one dimensional histogram 1DHIST or channel (X,Y) of a two dimensional histogram 2DHIST, respectively,  by VALUE. The default value of VALUE is 1. Only in special cases, e.g., if you want to do stability investigations or for the count rate in dependence of the measurement time, one should use other values.

The names and dimensions of the histograms are defined in the files hiscre_nng.scom, hisdef_nng.h and hisini_nng.h. To modify these settings one has to run the following command:

lea -mod nng

This will open a window, where all defined histograms are listed. The use of this program is self-explaining. Note that every entry has to be confirmed by pressing the ENTER-key and changed histogram has to be confirmed be clicking the "Apply" button. To save and leave the modifying program one has to click the buttons "Apply", "definition file", "Save", and "Quit" in this order.

To run the analysis one has to do the following steps (Note: every entry in LEA has to be confirmed by pressing the ENTER-key):

1. goto working directory on fwk28 ssh -X ntofdaq@fwk28
password: ***********
cd lea/nng
2. start LEA graphical interface lea -pro gn -men
3. choose data source if lmd file:
if MBS stream:
Source = LMD File; Input file/node = /data/filename.lmd
Source = MBS samples; Input file/node = rio7
4. start analysis click "Analyze events"

The following histograms are produced by LEA:

Name xmin xmax xbinsize ymin ymax ybinsize Meaning (x) Meaning (y) Meaning (z)
TDCPL 0 65536 10 0 15 1 TDC raw value
0 : accelerator
1...10 : plastic DAQch1...10
11 : trigger
counts
TDCBAF 0 32768 10 0 44 1 TDC raw value
0 : accelerator
1...42 : BaF2 DAQch1...42
43 : trigger
counts
QDC 0 4096 1 0 10 1 QDC raw value
0...9 : plastic DAQch1...10
counts
RATE1...3 0 10000 1 0 32 1 number of scaler readouts input channel of scaler 2...4 count rate = counts divided by time flag
ADC 0 4096 1       ADC raw value counts  
LGS 0 4096 1 0 43 1 LGS raw value
0...41 : BaF2 DAQch1...42
counts
SGS 0 4096 1 0 43 1 SGS raw value
0...41 : BaF2 DAQch1...42
counts
LG 0 4096 1 0 43 1 LG raw value
0...41 : BaF2 DAQch1...42
counts
SG 0 4096 1 0 43 1 SG raw value
0...41 : BaF2 DAQch1...42
counts
SUMTDC 0 65536 1 0 6 1 time of flight = (time sum of TDC values from both bases of one plastic - 2 x TDC value from accelerator)/2
0...5 : plastic detector 1...5
counts
SUMTDCS 0 6554 1 0 6 1 same as SUMTDC but divided by 10
0...5 : plastic detector 1...5
counts
SUMTDCS2 0 6554 1 0 6 1 same as SUMTDCS with a gate on DIFFTDC
0...5 : plastic detector 1...5
counts
DIFFTDC 0 2000 1 0 5 1 time difference between TDC values of both bases of one plastic without an accelerator hit
0...5 : plastic detector 1...5
counts
DIFFTDC2 0 2000 1 0 5 1 same as DIFFTDC but with accelerator hit found
0...5 : plastic detector 1...5
counts
TDCPLDIFF 0 32768 5 0 15 1 time difference to accelerator
0...9 : plastic DAQch1...10
counts
TDCBAFDIFF 0 32768 5 0 45 1 time difference to accelerator
0...41 : BaF2 DAQch1...42
counts
MULT 0 45 1       multiplicity of BaF2 crystals hit counts  
MULTPAT2 0 42 1 0 42 1 BaF2 DAQch BaF2 DAQch number of coincidences
TWODLGSG01...42 0 4096 12 0 4096 12 LG raw value of BaF2 DAQch1...42 SG raw value of BaF2 DAQch1...42 counts
LGSUM 0 8192 1       sum of all LG values per event counts  
QDCW1...3 0 4096 1 0 10 1 QDC value with different gates on SUMTDC
0...9 : plastic DAQch1...10
counts

Contact

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