Primex Meeting, Friday September 16, 2005
Present: McNulty, Ito, Hardy, Mochalov, Clinton, Wood, Teymurazyan.
On Phone: Dale, Gasparian.
Secretary: Clinton.
Review and approve old minutes.
New business:
1.) Mike Wood presented results on the ability of the veto to pick out
charged particles in 3 cluster events in Carbon. A combinatorial analysis
of all pairs of clusters was used. Summary of result is that the veto can
effectively distinguish between charged and neutral events, but does not
have a very significant ability to reduce background in the pizero
invariant mass spectrum. Mike's presentation is in slides directory at
http://www.jlab.org/primex/weekly_meetings/slides_2005_09_16/mhw_16sep2005/.
events.
Dan Dale suggested that his Monte Carlo regarding veto performance may be
irrelevant because his MC used the strip sum trigger, and production data
used the Total Sum. Suggested someone redo the MC with proper trigger.
2.) Dustin McNulty presented calibration of the elasticity of the
tungstate and glass, singly and mixed. His presentation is in the slides
directory for Sept 16 2005 at
http://www.jlab.org/primex/weekly_meetings/slides_2005_09_16/mcnulty/.
The summary : Tungstate's elasticity is 1% high, glass is 7% low, mixed
(Glass and Tungstate) is 4% low when tungstate most of the energy and 7%
low when glass has most of the cluster energy. The invariant mass seems,
when reconstructed in a similar group, appears to track these
mis-calibrations.
According to Vasiliy, lead glass calibration possible has a non-linearity
effect at low energy. This is possible due to a sparsification effect
where neighbors who share a small amount of the energy of the cluster are
removed from calibration for failing the sparsification cut.
3.) Marvin's talk at the Hawaii APS meeting will be/has been given by
Pedroni.
4.) Ashot Gasparian to Eric Clinton: get cracking on the tagger
calibration for the snake 1 and snake 2 scans. Eric to Ashot: Roger.
Wilco.
5.) Aram Teymurazyan presented a dry run of his APS talk on photon flux. A
lot of suggestions were made. His presentation is in the Sept 16 meeting
slides directory at
http://www.jlab.org/primex/weekly_meetings/slides_2005_09_16/aram_09_16_05/.
eric r.i. clinton
madpiper@physics.umass.edu
eclinton@jlab.org