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Dear Run Group B,</div>
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At long last we have produced the QADB for Pass 2 RG-B data, and released it on ifarm as 'qadb/3.2.0'. Many thanks to Derek Holmberg for carefully cross checking the results and helping with the effort.</div>
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We apologize that this has taken quite some time to finish; the main reason is that we have switched to performing the QA in "time bins" rather than binning by the DST files, and we have also added many new defect bits.</div>
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Please see the QADB documentation home page for the latest usage guidance: <a href="https://github.com/JeffersonLab/clas12-qadb?tab=readme-ov-file#clas12-quality-assurance-database" id="OWA73f0e6ee-85cd-207d-d0ba-de27662742df" class="OWAAutoLink">
https://github.com/JeffersonLab/clas12-qadb?tab=readme-ov-file#clas12-quality-assurance-database</a></div>
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Here are the major changes that impact user analysis:</div>
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<div>The Pass 1 QADB only used defect bits 0-9, whereas Pass 2 adds several new defect bits; see the table of defect bits in the link above</div>
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<div>The FC charge is now more accurate, because of the switch to "time bins":</div>
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<div>this resolves FC charge sum issue, identified in RG-A data but also very likely present in RG-B:
<a href="https://github.com/JeffersonLab/clas12-qadb/issues/48" id="OWA25a2cd78-a3d2-8263-8005-0059288f224f" class="OWAAutoLink">
https://github.com/JeffersonLab/clas12-qadb/issues/48</a></div>
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<div>it also fixes this one: <a href="https://github.com/JeffersonLab/clas12-qadb/issues/9" id="OWA9ddbb433-7103-476a-3403-a80cd2c1c637" class="OWAAutoLink">
https://github.com/JeffersonLab/clas12-qadb/issues/9</a></div>
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<div>the QADB code now provides a function 'QADB::CorrectHelicitySign' which provides the "correct" helicity sign for the data</div>
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<div>basically, 'true helicity' = 'helicity from cooked data' * CorrectHelicitySign(run_number, event_number)</div>
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<div>the correct helicity sign comes from the SIDIS pi+ beam-spin asymmetry sign; if it's wrong, the QA defect bit 'BSAWrong' is assigned and 'QADB::CorrectHelicitySign' returns '-1'</div>
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<div>this is especially important for RG-B data, since some of the datasets have 'BSAWrong' for many of the runs</div>
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<div>do not assume that all consecutive runs follow the same sign convention, as there may be specific runs which deviate from their neighboring runs; using 'QADB::CorrectHelicitySign' or 'BSAWrong' is preferred</div>
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For more information, see the release notes page: <a href="https://github.com/JeffersonLab/clas12-qadb/releases" id="OWA60b90fcc-aa08-cfce-014c-b3bb9fbb4e61" class="OWAAutoLink">
https://github.com/JeffersonLab/clas12-qadb/releases</a></div>
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To switch to the new 3.2.0 version, if it's not yet the default on ifarm, use:</div>
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module switch qadb/3.2.0</div>
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It's also available from the above GitHub repository.</div>
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Let me know if you have any questions or need any help,</div>
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Chris</div>
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<p style="margin-top: 0px; margin-bottom: 0px; font-family: Aptos;"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 10pt; color: rgb(0, 0, 0);">Christopher Dilks</span></p>
<p style="margin-top: 0px; margin-bottom: 0px; font-family: Aptos;"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 10pt; color: rgb(0, 0, 0);">Jefferson Lab Staff Scientist</span></p>
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