JB DAQ

From New IAC Wiki
Jump to navigation Jump to search

Back JB Analysis

DAQ commands

Source CODA and ROOT

source ~/CODA/2.6.2/setup 
source /home/daq/src/root/root-5.34.00/bin/thisroot.csh

Run the bash script titled 'jeff', which takes the run number as an argument. This script will automatically convert the .dat file to a .root file and then open it in root. The script: File:Jeff.txt.

bash jeff 4716

The first index of evt.TDC1190 is the hit #. The second index increases consecutively with TDC channel number, but the index starts from 1, while the TDC channels start at 0.

Common ROOT plot commands for copy-past:

First hit minus second hit:

 R1DC->Draw("(evt.TDC1190[2][16]-evt.TDC1190[1][16])")

PMT difference:

R1DC->Draw("(evt.TDC1190[1][2]-evt.TDC1190[1][3])/10","evt.TDC1190[1][2]!=0 && evt.TDC1190[1][3]!=0 && evt.TDC1190[1][1]!=0")

"ToF", where evt.TDC1190[1][16] is the trigger:

FF->Draw("(TDC.TDC1190[1][3]/10+TDC.TDC1190[1][4]/10)/2-TDC.TDC1190[1][16]/10>>ToF(1000,-200,800)","TDC.TDC1190[1][3]!=0 && TDC.TDC1190[1][4]!=0 && TDC.TDC1190[1][16]!=0")
R1DC->Draw("0.1*((TDC.TDC1190[1][3]+TDC.TDC1190[1][4])/2-TDC.TDC1190[1][25])>>ToF(1000,-200,800)","TDC.TDC1190[1][3]!=0 && TDC.TDC1190[1][4]!=0 && TDC.TDC1190[1][25]!=0")

TDC Calibration

The data was collected by taking the channel difference between two pulses with a delay of 500,600,700, and 800 ns.

DaqCali.png

Miscellaneous

Pace of signal

The pace of a signal in a 223/U cable is 1.5 ns/ft.

Backwards dead time of digital delay modules

When an input receives 2 or more pulses over a duration less than or equal to (the delay) + (the output pulse width) + (~0-20 ns), only the final pulse received during this duration will appear in the delayed output signal.

solution:

Connect one of the two available the outputs (OUT) to the VETO. This causes the device to reject multiple pulses during the delay duration, ensuring that the delay is constant with respect to the initial pulse.

CAEN N841 discriminator channel multiplicity

The device has an output in the rear labeled [math]\Sigma[/math] which outputs a 50*N mV signal, where N is the number of channels over threshold. This can be used to do coincidence counting such as "three of greater active channels", by feeding the [math]\Sigma[/math] output into a discriminator channel and setting the threshold accordingly.

NIM/ECL translator channel to ROOT channel

e.g. NIM/ECL channel 2A maps to evt.TDC1190[1][3]

NIM ECL2R1DC.png