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Dear collaborators,<br>
Please find H12700-H8500 comparison review here:
<a class="moz-txt-link-freetext" href="https://userweb.jlab.org/~kenjo/H12700report.pdf">https://userweb.jlab.org/~kenjo/H12700report.pdf</a><br>
<br>
"Short" summary: <b>H12700 is still better than H8500 due to the
higher photocathode quantum efficiency.</b> The nearly uniform
illumination of pixel shows that SPE spectrum is not as good as it
was anticipated. It has more complicated structure than H8500. The
structure was described using Pavel Degtiarenko's model, and using
his model's fit results the collection efficiency was estimated for
both MAPMT types. The H8500 demonstrated higher collection
efficiency than H12700 (unexpected and rather saddening behaviour).
Fortunately, H12700 has higher photocathode quantum efficiency, and
it was determinative factor in H12700 superiority.<br>
Please note that separation of quantum and collection efficiencies
is possible <b>within model framework only.</b> However, the <b>global
efficiency (decisive criteria)</b> is model independent as it is
the fraction of events with signal over pedestal's 5 sigma
(assuming, of course, that light source is stable and constant).<br>
Any comments, suggestions or corrections are welcome!<br>
Thank you!<br>
<br>
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