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Hi all,<br>
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<br>
I thought I'd update you on the neutron path corrections before I go on holidays tomorrow. I've attached some slides on these path corrections extracted for RG-B spring2019 data. Some comments on these:<br>
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I used two datasets for this, spring2019 RG-B and RG-A. In principle RG-A should be calibrated the same way, the difference in RG-B is that the assumption of a stationary proton is going to introduce some smearing to my missing neutron components. However,
judging from the path differences in slide 5, the RG-A dataset seems suitable to extract corrections for RG-B. Two other suggestions were to look at the quasi-elastic ed->e’n(p) with the possibility of maybe detecting some of the spectator protons (or again
to make the assumption of a stationary neutron) or to look at ed->e'npi+pi-p. I haven't had a chance to look at the former, for the latter most neutrons seem to be in the CD but this might not be the case for low beam energy runs (such as the ones used for
BAND calibration at 4.4 GeV) as in g10 analyses there seemed to be a good signal of neutrons in the FD.<br>
<br>
Also, compared to what I showed <a href="https://clasweb.jlab.org/wiki/images/5/5b/09_07_21.pdf" title="https://clasweb.jlab.org/wiki/images/5/5b/09_07_21.pdf">
last week</a>, I haven't corrected the timing info used to recalculate Beta. The reason why I chose not to do this is first that as you can see in my slides from last week using or not these time corrections doesn't have much of an effect on the corrected Beta
value. Secondly there's still quite a few things that aren't well understood with these timing corrections. Kayleigh Gates who's also doing a PhD in Glasgow is planning on having a more in depth look into issues with path and timing calibration/reconstruction
for the calorimeters in general. In the meantime the corrections I suggest in my final slide should work as far as I can tell, although this is obviously not the final picture.
<br>
<br>
When I get back from holidays, I'm planning to check the effect these corrections have on my ed->(e') J/psi n(p) analysis. If anyone has time to try these out or to do any cross checks by then I'd be happy to hear from you on this!<br>
<br>
Cheers,<br>
Richard<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Clas12_rgb <clas12_rgb-bounces@jlab.org> on behalf of Silvia Niccolai <silvia@jlab.org><br>
<b>Sent:</b> 14 July 2021 21:25<br>
<b>To:</b> clas12_rgb@jlab.org <clas12_rgb@jlab.org><br>
<b>Subject:</b> [Clas12_rgb] RGB meeting this Friday?</font>
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<div class="PlainText">Hello all,<br>
I may not be able to host this Friday’s RGB meeting because I am away on holiday until Saturday. If there are pressing items to present please let me know, and someone else (Bryan, Stepan, Adam, or whoever if available) can host the meeting. Otherwise, we’ll
resume next week. <br>
Thanks a lot and best regards, <br>
Silvia<br>
<br>
Sent from my iPhone<br>
<br>
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