[G8b_run] Fwd: g8b TOF paddles

[Eugene Pasyuk]

 From Brian.

-------- Original Message --------
Subject: 	g8b TOF paddles
Date: 	Sun, 24 Jul 2011 22:29:47 -0400
From: 	Brian Vernarsky <soulish at gmail.com>
To: 	Eugene Pasyuk <pasyuk at jlab.org>



Eugene, I have been subscribed to g8b_run but for some reason it will
not let me send messages.  I have written this up to send to the list
could you please forward it for me?  Thanks, Brian

Hi all,

I have recently started looking at g8b, the omega channel, and noticed
that I am losing half of my signal to events that have at least one
particle that hit a TOF paddle that was marked as bad in the cooking.
The bad paddles are detailed on the g8b TOF calibration page as can be
seen here: http://www.jlab.org/Hall-B/secure/g8b/TOF_CALIB/g8b_TOFcalib.html.

I don't know much about the TOF calibration or the rationale behind
excluding these paddles beyond what is on that webpage, but given that
the paddles did record events, as can be seen in ced, it seems like it
would be very beneficial to recook the data to recover these otherwise
completely fine events, especially because it means we could almost
double the statistics in certain topologies, omega being the only one
I've actually looked into.

I have written up a pdf showing the problem and showing some events
that are lost due to this problem in ced to show that a particle was
in fact detected and that we could perhaps recover the event.  You can
find it at the following location:

https://www.andrew.cmu.edu/~bvernars/g8_tof_prob.pdf

Again let me say that I don't know anything about the TOF calibration
that goes into the cooking and so if there are valid reasons for all
these paddles to be excluded please let me know and I'll be happy to
include that info into the Monte Carlo.  But if it possible to recover
some of these lost events it seems worthwhile to look into it.

Thanks for your time,

Cheers,

Brian

-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://mailman.jlab.org/pipermail/g8b_run/attachments/20110724/0b7a4639/attachment.html