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    Folks,<br>
    <br>
    Please find the minutes below and at<br>
    <br>
     
<a class="moz-txt-link-freetext" href="https://halldweb1.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_December_12,_2014#Minutes">https://halldweb1.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_December_12,_2014#Minutes</a><br>
    <br>
      -- Mark<br>
    _________________________________________<br>
    <br>
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          GlueX Start Counter Meeting, December 12, 2014<span
            class="mw-headline" id="Minutes">, Minutes</span><br>
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            <br>
            Present:
            <br>
            <ul>
              <li> <b>FIU</b>: Werner Boeglin, Mahmoud Kamel, Eric
                Pooser
              </li>
              <li> <b>JLab</b>: Mark Ito, Beni Zihlmann
              </li>
            </ul>
            <br>
            <span class="mw-headline" id="Online_Monitoring_Histograms">Online
              Monitoring Histograms</span><br>
            <br>
            Eric has been looking at the histograms to check status of
            the start counter. He has some suggestions for histograms
            that should be pulled out and put into the "highlights" list
            for the online monitoring browser. He will send Justin an
            email with the list.
            <br>
            <br>
            <span class="mw-headline" id="Start_Counter_Studies">Start
              Counter Studies</span><br>
            <br>
            Eric presented <a
href="https://halldweb1.jlab.org/talks/2014-4Q/ST_Update_Dec_12_2014.pdf"
              class="external text" rel="nofollow">some slides</a> on
            recent work to understand the data we are getting from the
            start counter. We had extensive discussion on each slide.
            The main themes were:
            <br>
            <ul>
              <li> <b>Timing</b>. Now that he is using the reference
                signal to the F1-TDCs, reasonable timing results were
                shown.
              </li>
              <li> <b>Tracking Projections</b>. The intersection points
                of charged tracks and the start counter are generally
                sensible, but in detail present many anomalies.
              </li>
            </ul>
            <br>
            <span class="mw-headline" id="Calibration">Calibration</span><br>
            <br>
            We identified the front-burner issues:
            <br>
            <ul>
              <li> better understanding of charged track projections
              </li>
              <li> counter-by-counter time offsets
              </li>
            </ul>
            <br>
            Precision on the latter will depend on the former.
            <br>
            <br>
            <span class="mw-headline" id="The_Sector_2_Blues">The Sector
              2 Blues</span><br>
            <br>
            Eric has noted consistently lower rates in sector 2 compared
            to the others going back to the early days of the run. The
            raw ADC and TDC spectra and occupancy do not explain it.
            More investigation is needed.
            <br>
            <br>
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              Retrieved from "<a
href="https://halldweb1.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_December_12,_2014">https://halldweb1.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_December_12,_2014</a>"</div>
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    <pre class="moz-signature" cols="72">-- 
Mark M. Ito, Jefferson Lab, <a class="moz-txt-link-abbreviated" href="mailto:marki@jlab.org">marki@jlab.org</a>, (757)269-5295</pre>
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