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<p class="MsoNormal">I think it must be a typo in the Table 27, it should be 5.7 rather than 1.7 for the flux uncertainty.<o:p></o:p></p>
<p class="MsoNormal">Normalization uncertainty is coming from run-to-run variation of the normalized yield. Flux uncertainty is global uncertainty of flux. As I recall it came from variation of tagging ratio from different normalization runs. It is a single
scaling factor for the entire tagging range.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-Eugene<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b>From:</b> Volker Crede <vcrede@fsu.edu> <br>
<b>Sent:</b> Monday, September 14, 2020 16:40<br>
<b>To:</b> g12 <g12@jlab.org><br>
<b>Cc:</b> Eugene Pasyuk <pasyuk@jlab.org><br>
<b>Subject:</b> [EXTERNAL] CLAS-g12 flux / normalization uncertainty<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="color:black">Dear Colleagues,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="color:black">I am currently working on the referee report for our g12 eta paper and I stumbled over the following issue. On Page 94 of our run-group note (CLAS-NOTE 2017-002), it says that
<i>we should stick to the currently quoted lower bound of the systematic uncertainty for the g12 normalization of 5.7%.</i><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal">Later in Table 27, we quote a flux uncertainty of 1.7% and a normalization uncertainty of 1.8%<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Can somebody clarify the situation? <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">1. Where does the flux uncertainty of 1.7% come from?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">2. How is the flux uncertainty different from the normalization uncertainty?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">3. What have others used or what will others use for these uncertainties in their papers?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Best wishes,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"> Volker<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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