Difference between revisions of "Photon Reconstruction 07/16/2012"

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* Even after timing cuts, still have large background under pi0 peak.
+
===Problem===
 +
Even after timing cuts, still have large background under pi0 peak.
  
 
[[File:2gamma.invariantmass.b1pi.png]]
 
[[File:2gamma.invariantmass.b1pi.png]]
  
 
+
===Splitoffs?===
 
* [[Splitoff_Information | Splitoff suppression in Crystal Barrel, CLEO]]
 
* [[Splitoff_Information | Splitoff suppression in Crystal Barrel, CLEO]]
** Various discriminators to distinguish between
+
** Various discriminators to distinguish between splitoffs, photons
 +
*** Distance/angle between potential parent cluster and potential splitoff
 +
*** Energies of parent and splitoff
 +
*** E9/E25 [[File:E9.E25.png|50px]]
 +
*** Left-right/up-down asymmetry  [[File:Fcal.asym.png|50px]]
 +
** Feed this into a neural net to determine splitoff probability
 +
** Alternate FCAL clustering to minimize splitting of hadronic showers (naive algorithm just to group together neighboring hits)
 +
 
 +
===BCAL?===
 +
 
 +
===What's next===
 +
Better understand origin of these extra clusters.

Latest revision as of 11:07, 16 July 2012

Problem

Even after timing cuts, still have large background under pi0 peak.

2gamma.invariantmass.b1pi.png

Splitoffs?

  • Splitoff suppression in Crystal Barrel, CLEO
    • Various discriminators to distinguish between splitoffs, photons
      • Distance/angle between potential parent cluster and potential splitoff
      • Energies of parent and splitoff
      • E9/E25 E9.E25.png
      • Left-right/up-down asymmetry Fcal.asym.png
    • Feed this into a neural net to determine splitoff probability
    • Alternate FCAL clustering to minimize splitting of hadronic showers (naive algorithm just to group together neighboring hits)

BCAL?

What's next

Better understand origin of these extra clusters.