[Halld-pid] Time-of-Flight Meeting Minutes, March 18. 2015

[Mark Ito]

Folks,

Find the minutes below and at

https://halldweb.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_March_18,_2015#Minutes

   -- Mark
___________________________________


GlueX TOF Meeting, March 18, 2015, Minutes

Present:

  * *FSU*: Paul Eugenio
  * *JLab*: Mark Ito (chair), Sasha Ostrovidov, Beni Zihlmann
  * *NU*: Sean Dobbs


Calibration Status

Sasha showed plots 
<http://hadron.physics.fsu.edu/%7Eostrov/tof/20150317/> illustrating one 
of the difficulties he is having with the outer counters of the 
detector. For front-back coincidences, he shows x determined by the 
known location of the counter in the back plane vs x determined by time 
difference in the front plane. For module 19 in the front, near the 
middle of the array, the correlation is clear and time difference easy 
to calibrate. For module 0 at the edge the statistics are much less and 
there are a lot more uncorrelated hits.
Sasha is still formulating a plan for calibration of the short paddles. 
Since they are in the middle of the array, their occupancy is high and 
calibrating them is important.

TOF Reconstruction Performance

Sean showed some plots 
<https://halldweb.jlab.org/wiki/images/4/4b/TOF_Meeting_2015-03-17.pdf> 
showing widely varying charged-track matching efficiency with charged 
tracks for two nearby runs from the Fall run. Even for the "good" run 
the match efficiency is not so great. For the "bad" run, there are very 
few good TOF hits from the hit factory to begin with. Beni thought that 
this might be due to the entire time frame shifting between runs due to 
trigger changes. If so it emphasizes the importance of keeping track of 
trigger changes, especially where the timing is affected.

Retrieved from 
"https://halldweb.jlab.org/wiki/index.php?title=GlueX_TOF_Meeting,_March_18,_2015&oldid=64258"

-- Mark M. Ito, Jefferson Lab, marki at jlab.org, (757)269-5295
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/halld-pid/attachments/20150318/f5d3115e/attachment-0002.html>