Since the PMs of the CEDARS are up to 25 years old, one asked for the performance of
the PMs. This was exactly my job for my diploma thesis in the year 2006. I needed to
record the PM signals and to perform some statistics. All existing solutions needed a huge
infrastructure of hardware and a strange mixing of different standards like CAMAC, NIM and
VME for the readout of TDC and ADC information with existing modules. The readout was also
not so easy. But I wanted to have as less hardware as possible and I needed to be as
portable as possible.
The solution: All needed information was processed by osciloscopes.
To access this information, the TDS 3000 series by
Tektronix offer a wonderfull interface
via network connection. One can readout the Signal and store it in files, but not instantan.
To perform statistical treatment of this signals I wrote a program that communicates, using
the ActiveX interface from Tektronix under Microsoft Windows. This program can be found in
the downloads area and is for free.
Of course I can't be charged for any damages caused by this software.
The software reads the waveforms, separates them from flat Baseline and stores the waveforms
in a Zip-folder. It also calculates rise time, fall time, FWHM, FW10M, max pulse height,
transit time at mass centre, integral (equ. ADC information) normalized to 1 Coulomb
and leading edge events. After dataaquisition one can transform all calculated data to a
ROOT file with stored values as ntuple. This way you are able to perform cuts on the data.
The TDS 3000 series feature a 10Mbit Network connection. This means about 3 Readouts/s.
I had the expirience that about 1500 wavforms were enougth for good distributions.
Every measurement took about 10 minutes. If you have Events, that are triggered just as
a fraction of all triggered events, this means a loss of performance. That is you only record a
fraction of usefull events. To enhance the readout try:
- rise the signal to noise relation by higher source rates
- trigger on coincidences between source and readout detector
- Use the single event setting of the osciloscope to avoid flat line readout
- Use fast aquire mode of the osciloscope to reduce the waformlength.
A complete documentation is attached to my diploma thesis, that can be also found here , and is in written in german. For all not germans in the world here short introduction:
- Windows XP SP2 running on a PC with Networkconnection
- Network cable (Crossed for direct coupling to PC)
- TDS-Readout-Software [newest vers.]
- Tektronix osciloscope with network connection [TDS 3000 series]
- TekVISA Ressource Manager [vers. 2.03] (can be found at
Tektronix website)
- ROOT
software for Windows [vers. 5.12] (optional for creating *.root files)
- Gnuplot for Windows [vers. 4.0] (optional for enhanced display)
- Rootalias Makro [1.3.0] (included in TDS-Readout-Software needs ROOT installed)
I can't keep this part up to date due to fast soft- and hardware changes and other setups may also work. The software performed negative PMT and HPMT signals. Please simply try out.
Install all software (Gnuplot and Rootalias Makro has not to be installed) connect Tektronix
osciloscope to network and do so with the PC. Setup matching IP and Subnetmask settings and
try to launch the TekVISA Ressource Manager. One can check the connection easily by typing
the IP Adress of the osciloscope into a Web-Browser. The osciloscope has a a web interface
that should apear. If this works TekVISA should be able to establish a connection. This will
be showed you.
Now you can launch the TDS readout program. Just determine a session. Then go to the options
and set all needed paths. Than you can start. More about the program, as allready mentioned
you can find attached to my diploma thesis.