<html>
  <head>

    <meta http-equiv="content-type" content="text/html; charset=utf-8">
  </head>
  <body text="#000000" bgcolor="#FFFFFF">
    <p>Folks,</p>
    <p>Find the notes below and <a moz-do-not-send="true"
href="https://halldweb.jlab.org/wiki/index.php/HDGeant4_Meeting,_July_20,_2018#Notes">here</a>.</p>
    <p>  -- Mark</p>
    <p>________________</p>
    <p>
    </p>
    <div id="globalWrapper">
      <div id="column-content">
        <div id="content" class="mw-body" role="main">
          <h1 id="firstHeading" class="firstHeading" lang="en"><span
              dir="auto">HDGeant4 Meeting Notes, July 20, 2018</span></h1>
          <div id="bodyContent" class="mw-body-content">Present:
            <div id="mw-content-text" dir="ltr" class="mw-content-ltr"
              lang="en">
              <ul>
                <li> <b> FSU: </b> Sean Dobbs</li>
                <li> <b> JLab: </b> Alex Austregesilo, Thomas Britton,
                  Mark Ito (chair), Justin Stevens, Simon Taylor, Beni
                  Zihlmann</li>
                <li> <b> Regina: </b> Zisis Papandreou</li>
                <li> <b> UConn: </b> Richard Jones</li>
              </ul>
              <p>There is a <a rel="nofollow" class="external text"
                  href="https://bluejeans.com/s/PCm4D/">recording of
                  this meeting</a> on the BlueJeans site. Use your JLab
                credentials.
              </p>
              <h3><span class="mw-headline"
                  id="Review_of_notes_from_last_time">Review of notes
                  from last time</span></h3>
              <ul>
                <li> <a
href="https://halldweb.jlab.org/wiki/index.php/HDGeant4_Meeting,_July_6,_2018#Notes"
                    title="HDGeant4 Meeting, July 6, 2018">Notes</a>
                  were reviewed</li>
              </ul>
              <h3><span class="mw-headline"
                  id="Review_of_first_round_of_simulation_results">Review
                  of first round of simulation results</span></h3>
              <ul>
                <li> Thomas showed <a rel="nofollow" class="external
                    text"
                    href="https://halldweb.jlab.org/gluex_sim/G3G4_Comparisons/ver01/">list
                    of plots</a>.
                  <ul>
                    <li> <a rel="nofollow" class="external text"
href="https://mailman.jlab.org/pipermail/halld-offline/2018-July/003259.html">email
                        announcement of plots</a></li>
                  </ul>
                </li>
                <li> Much time spent discussion of one plot:</li>
              </ul>
              <p><a
href="https://halldweb.jlab.org/wiki/index.php/File:Prot_4_15_Hist_Reconstruction.png"
                  class="image"><img alt="Prot 4 15 Hist
                    Reconstruction.png"
src="https://halldweb.jlab.org/wiki/images/9/9f/Prot_4_15_Hist_Reconstruction.png"
                    height="628" width="800"></a>
              </p>
              <ul>
                <li> Sean: geometry could be the cause</li>
                <li> Richard: would like help isolating problem to
                  simulation or to reconstruction
                  <ul>
                    <li> Thomas will put together a plug-in to explore</li>
                  </ul>
                </li>
                <li> Thomas: both FDC and CDC hits are missing</li>
                <li> question: are truth hits along real track
                  trajectory
                  <ul>
                    <li> can be explored with event viewer</li>
                    <li> Beni volunteers</li>
                  </ul>
                </li>
                <li> This is an <a rel="nofollow" class="external text"
href="https://github.com/JeffersonLab/HDGeant4/issues/54">issue on
                    GitHub</a></li>
              </ul>
              <h3><span class="mw-headline" id="Other_Issues">Other
                  Issues</span></h3>
              <ul>
                <li> Maria Patsyuk <a rel="nofollow" class="external
                    text"
href="https://groups.google.com/forum/#%21topic/gluex-software/VOnAjfCf3r4">reported
                    overlaps in the geometry</a>
                  <ul>
                    <li> Richard will work on this</li>
                  </ul>
                </li>
                <li> Richard: issues with roll-your-own event generators
                  <ul>
                    <li> interaction z and t are correlated by machine
                      bunch structure</li>
                    <li> decay of long-lived particles can lead to
                      double counting (parent and daughter particles
                      both appear in final state)</li>
                    <li> [added in press] Richard wrote <a
                        rel="nofollow" class="external text"
href="https://halldweb.jlab.org/wiki/index.php/Guide_to_Monte_Carlo_event_timing_and_detached_vertices_in_HDGeant/4">new
                        wiki page describing best practices</a>.
                      <ul>
                        <li> There is a <a rel="nofollow"
                            class="external text"
                            href="https://github.com/JeffersonLab/HDGeant4/issues/55">related
                            issue on GitHub</a></li>
                      </ul>
                    </li>
                  </ul>
                </li>
                <li> Sean added an additional plot on the <a
                    rel="nofollow" class="external text"
                    href="https://github.com/JeffersonLab/HDGeant4/issues/10">time
                    shift in FCAL showers issue</a>. He sees a
                  difference in hit times vs. shower times.</li>
              </ul>
              <h3><span class="mw-headline" id="Meeting_Time">Meeting
                  Time</span></h3>
              <p>No one objects to meeting on Tuesdays at 2 pm, every
                other week.
              </p>
            </div>
            <div class="printfooter">
              Retrieved from "<a dir="ltr"
href="https://halldweb.jlab.org/wiki/index.php?title=HDGeant4_Meeting,_July_20,_2018&oldid=88358">https://halldweb.jlab.org/wiki/index.php?title=HDGeant4_Meeting,_July_20,_2018&oldid=88358</a>"</div>
          </div>
        </div>
      </div>
      <div id="footer" role="contentinfo">
        <ul id="f-list">
          <li id="lastmod"> This page was last modified on 21 July 2018,
            at 12:54.</li>
        </ul>
      </div>
    </div>
  </body>
</html>