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<u><b>Oscar:</b></u> Looking at Q2, nu, and W distributions for
parallel data. Was getting some values of W2<0 and asking if this
could be due to a problem with obtaining Q2 in the physics ntuple.
Also noticed that about ~10% of nu came out as 0. The negative W2
values seem to be from rescattering. <br>
<br>
Hovhannes mentioned that he had adjusted the cuts in the Replay and is
about to update the CVS version with them. The naught nu values were
from events not passing the necessary cuts, but are being kept in so
that quantities such as angle and energy can be recovered. <br>
<br>
<a class="moz-txt-link-freetext" href="http://www.jlab.org/~rondon/sane/analysis/replay/?M=D">http://www.jlab.org/~rondon/sane/analysis/replay/?M=D</a><br>
<br>
<br>
<u><b>Hovhannes:</b></u> Extracted polynomial coefficients for no field
data. Improved the pi0 calibration to where it has a resolution of
better than 7-9% depending on how background is fit. <br>
<br>
Gave intermediate calibration constants to Anusha. Elastic peak seems
to have a shift of ~400MeV. Also, Anusha's Replay seems to have a
secondary peak in y (don't recall which specific variable this is);
one at 0cm and one at 50cm. Hovhannes asked if it could be from either
the sieve slit correction or the momentum reconstruction from HMS. Mark
mentioned that the HMS P reconstruction is well known and that he and
Anusha would look further into this. <br>
<br>
<br>
<u><b>James:</b></u> Looking at particle tracking and constraining to
the front tracker. Looked at the x and y values for the tracker,
lucite, and clusters. Saw that about 90% of cases for 2 lucite bars
being hit the bars were adjacent to each other, which seems to make
sense. The tracker-y seems to be approximately half as efficient, which
also seems reasonable. Will look with updated Replay when it's checked
into CVS and use track fitting routine that is in Replay for higher
energies, where it should have mostly electrons with minimal bending. <br>
<br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Particle_Tracking_to_Front_Tracker%2C_Target">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Particle_Tracking_to_Front_Tracker%2C_Target</a><br>
<br>
<br>
<u><b>Jon:</b></u> Looking at events with 2 clusters and 1 Cerenkov
mirror hit. Sees narrow separation between clusters in x (~3cm) and
wider in y (~10cm), but still not far away from the clusters
overlapping. Will try fixing energy of one cluster while cutting on the
other's to see if it's possible to see e-e+ pairs.<br>
<br>
Looked at Cerenkov ADC spectrum for cases of 1 and 2 clusters. For the
2 cluster spectrum there appears to be evidence of a 2nd photon peak.
Will try subtracting (normalized) spectrum of 1 cluster from 2 cluster
spectrum to pick out secondary peak.<br>
<br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Jrm_double_clust">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Jrm_double_clust</a><br>
<br>
<br>
<u><b>Whit:</b></u> Looking at various algorithms that could be used
for clustering for the neural network.<br>
<a class="moz-txt-link-freetext" href="http://quarks.temple.edu/~whit/code/InSANE++/html/group__Clustering.html">http://quarks.temple.edu/~whit/code/InSANE++/html/group__Clustering.html</a><br>
<br>
<br>
As always, please let me know if I missed something or got it wrong.<br>
<br>
<br>
Next meeting will be May 5th at 3:30 pm. <br>
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