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<font face="Helvetica, Arial, sans-serif">Dear g12 colleagues,<br>
</font>
<div class=""><font face="Helvetica, Arial, sans-serif">I write you
to inform that, after a long time passed after my PhD thesis
defense, that included a (preliminary) analysis of the gamma p
-> p pi0 eta reaction from CLAS-g12 data, I decided to resume
this analysis, starting from scratch and following closely the
g12 procedures highlighted in the official g12 note. In the
analysis, I am identifying pi0 and eta via the gamma-gamma
decay.<br>
</font></div>
<div class=""><font face="Helvetica, Arial, sans-serif">This will be
a low-priority project for me, but I’d like to come to an end of
it - from what I saw in the thesis, this channel is very
promising. Now, given the huge improvements in g12 analysis that
the g12 group did, I think it will be simpler to come to an end
of the analysis.</font><font face="Helvetica, Arial, sans-serif">I’d
like to inform you - just to double check if there is anyone
else looking at this reaction.</font><br>
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<font face="Helvetica, Arial, sans-serif"></font>
<div class=""><font face="Helvetica, Arial, sans-serif">I have just
started the analysis, and I am in the phase of selecting a good
sample of exclusive p pi0 eta events. Meanwhile, I also started
MC generation. At some point in the next future, I’d like to
show some progresses in one of the bi-weekly meetings, in order
to get your feedback from this.<br>
<br>
I already have a simple question regarding MC. I followed
closely the procedures highlighted in the g12 note to generate a
phase-space MC sample (I followed the procedures highlighted for
"proton, pi+, pi-", not those for "electrons and positrons"). In
the real data, if I plot the invariant mass of a photon pair, I
see a pi0 peak at around 135 MeV. However, If I do the same for
MC events, I see a peak at about 116 MeV. I also plotted the
reconstructed photon energy over the generated photon energy,
and I see a peak at around 0.87. It looks the simulation of EC
response in MC is not completely correct. (I confirm that the
peak for generated events is at 135 MeV)<br>
Is it because, using the EC, I should follow the procedure
highlighted for "electrons and positrons" (involving run number
10 and requiring </font>setenv CLAS_CALDB_RUNINDEX
calib_user.RunIndexg12_mk?)<br>
<br>
<font face="Helvetica, Arial, sans-serif">I also have a question
regarding the TOF knockout procedure. In the note, the relevant
method to use is: </font>clas::g12::pass_g12_<span
class="highlight selected">TOF</span>KO(int sector, int scid,
bool all_ko = 0), <font face="Helvetica, Arial, sans-serif">that
requires to know the counter ID. For a charged particle, from
the PART bank I can retrieve the entry in the TBID bank, and
from this to the SCRC bank, that, however, contains information
regarding TOF clusters. From this bank, I don't see a pointer to
the SCR bank - containing individual paddles data.<br>
<br>
Thanks,</font><br>
</div>
<br>
<div class=""><font face="Helvetica, Arial, sans-serif">Bests,</font></div>
<font face="Helvetica, Arial, sans-serif">Andrea</font><br class="">
<br class="">
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