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Igal,<br class="">
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<div class="">On Apr 16, 2020, at 6:46 AM, Igal Jaegle <<a href="mailto:ijaegle@jlab.org" class="">ijaegle@jlab.org</a>> wrote:</div>
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I am just removing the random coincidence below and in the peak of the prompt coincidence with the usual technique.
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<div>I think this only removes a background if the beam photon enters into your analysis. If the beam photon does not enter your analysis, then it doesn't matter whether it is accidental or prompt. How do you use the beam photon in your analysis?</div>
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<div>I think the trigger bit is indeed very important. If a substantial number of your triggers are FCAL + CCAL then these can almost never, by construction, provide the pi0 you desire for calibration and will only add background. And I believe they will
tend to contaminate inner layers most.</div>
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<div>Thanks... I'm just trying to see if there is some lesson from this that can be propagated back to the standard calibration method.</div>
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<div>Matt</div>
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