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Detecting Muons w/ an Oscilloscope

  1. Jul 25, 2012 #1
    I'm trying to detect muons. I have two big scintillators, roughly 2900 cm^2 surface area. We also have sensitive PMTs and oscilloscopes. Right now, we are just trying to pick up a signal that a muon passed through, but there is too much noise and we have not had any consitency.

    I guess my main question is, do you need a circuit board such as the Quarknet DAQ board to process the data in order to be able to see the significant signal? Or can it be read off the oscilloscope just fine? The answer so that question will help me know if the problem is with the setup or the problem is that I actually need the DAQ board to see the signal.
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  3. Jul 25, 2012 #2


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    How do you use the oscilloscope?
    Do you use any coincidence setup, i.e. only detect events where both scintillators see something nearly at the same time?
  4. Jul 25, 2012 #3
    I use it bare bone. Excuse the pun, but I just connect the scintillator/PMT with the BNC cable directly to the oscilloscope.

    I don't use a coincidence setup, I would need a circuit board for that such as the Quarknet DAQ board. I just figured that I can nevertheless pick up a signal either way, but just have more noise as a side effect. Feel free to correct this however.
  5. Jul 25, 2012 #4

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    You need to put one scintillator into one channel and trigger on it, and then display the other. Personally, I would not do it this way - the raw signal is too ragged. I'd run both through discriminators.
  6. Jul 25, 2012 #5
    Yes, I'm currently doing some research on various trigger techniques. I was completely ignorant of the concept of trigger until a couple of hours ago!

    Assuming you mean the rising end when you say ragged, that shouldn't pose too much of a problem once I incorporate a couple of the trigger techniques. But please enlighten me on this.

    I would love to slap a Quarknet DAQ board to discriminate the signals, but my mentor wants me to do this without the board.

    Now when you say you would run both through discriminators, you are speaking about circuit boards such as Quarknet or something else?

    Edit: Actually, I might be able to add 2-fold coincidence to trigger conditions by Boolean logic (AND) in trigger options. I'll check it out tomorrow.
    Last edited: Jul 25, 2012
  7. Jul 26, 2012 #6
    This thread mentions the term Quarknet DAQ board a lot.
  8. Jul 26, 2012 #7
    What are you trying to imply?

    So I've had some progress today, I was able to extract the significant signal out of the noise with a couple of triggers. But the oscilloscope is being a bit difficult as it wouldn't let me run trigger on both channels at the same time. I'm going to read the manual (just got got the manual today, would have been more helpful a little bit earlier lol) front to back and see if I can tweak everything a bit better.

    I also have to find out the output pulse that should be expected from the PMT so that I can know with an arbitrary amount of certainty that it is a muon passing through.
    Last edited: Jul 26, 2012
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