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Hi Pierre,
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<div class="">The slides look very nice! Just a couple of thoughts.</div>
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<div class="">Slide 3: Two-gluon exchange is necessary for the process to be “tube-iike” (where 1/Q is the “diameter”) rather than point-like as for a form-factor measurement, but near threshold t_min is large and the skewness (momentum difference between the
two gluons) has to be large. In the text it sounds like the gravitational form factor and gluon GPDs can be measured in the same kinematics. Perhaps one can say that one can access gluon GPDs though charmonium production at higher energies, away from threshold?</div>
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<div class="">Slide 19: You write that "Our results are not sensitive to th flattening at small Eγand large t seen by GlueX,” but maybe what you mean is that we are sensitive to such features, but don’t see them? :)</div>
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<div class="">The results on pages 20-21 are very nice and interesting. I still think it would be cool if one could show that the impact of the CLAS data in terms of the shape. Perhaps one could plot a ratio as well as the points themselves? It might also be
interesting to see what a fit to both sets would give (maybe with some renormalization to a common average)? Just seeing a lot of points can be hard to digest.</div>
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<div class="">Best,</div>
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<div class=""><span class="Apple-tab-span" style="white-space:pre"></span>Pawel</div>
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<div class="">On Mar 8, 2024, at 3:30 PM, Pierre Chatagnon via Clas12_dileptons <<a href="mailto:clas12_dileptons@jlab.org" class="">clas12_dileptons@jlab.org</a>> wrote:</div>
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Hello all,</div>
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I will present the JPsi analysis at the collaboration meeting next week. I attached the slides that I intend to show to this email.</div>
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They are essentially what I showed at the DPWG meeting a month ago with new additions: </div>
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on slides 9 I added a plot of the phase space that we cover</div>
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<span class=""> on slides 20 I added a plot with a comparison of the mass radius extracted by Hall C, GlueX and CLAS12</span><br class="">
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<span class="">Please let me know your comments/corrections</span></div>
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<span class="">Best</span></div>
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<span class="">Pierre</span></div>
<span id="cid:CA7D365A-8661-4EED-8BCF-D740625C4126"><JPsi_Photoproduction_CS_update.pdf></span><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">_______________________________________________</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
<span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Clas12_dileptons
mailing list</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
<a href="mailto:Clas12_dileptons@jlab.org" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">Clas12_dileptons@jlab.org</a><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
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