Status of OnboardFilter

1
Status of OnboardFilter

• Using release v9r9
• OnboardFilter v4r0p2
• Only wrapper code (OnboardFilter.cxx is in src
  now)
• Filter code is now an external package (work done
  by Tracy, Navid, Toby, etc)
• Package is called obf
• Has all of the libraries, including libraries
  which are loaded at run time
• Pedestals, calibs, geometry, etc
• Detailed comparisons to previous releases still
  in progress

2
Addition of BestTrack to OnboardFilter

• OnboardFilter algorithm computes 2D projections
  filter vetoes are based only on these, not on 3D
  combination
• Onboard Science (grb identification) needs 3D
  tracks
• Loop over XZ and YZ projections
• Require projections start in the same layer
• BestTrack defined to be that 3D combination
  with the largest number of total hits

3
Comparison of ground tracks to BestTrack

• Loop over ground tracks
• Find the track closest in XZ slope to the
  BestTrack
• Plot the difference in XZ/YZ slopes

4
Comparison to MC

• Using a sample of photons from GRBs
• Plot difference in XZ slope of MC gamma and
• bestTrack (lower plot)
• Ground track (upper plot using the ground track
  closest to the bestTrack)

5
Comparison to MC

• Using a sample of photons from GRBs
• Plot difference in YZ slope of MC gamma and
• bestTrack (lower plot)
• Ground track (upper plot using the ground track
  closest to the bestTrack)

6
Plans

• BestTrack algorithm is already being tested with
  Onboard science GRB identification/localization
• Need to update CVS with BestTrack code
  modifications to OnbaordFilter.cxx
• Add results of bestrack to Merit?