BkgTreePlotter

The BkgTreePlotter package provides tools to visualise the MC true origin of a background candidate (which works as well for signal candidates). It has been presented https://indico.cern.ch/event/355690/contribution/3/material/slides/0.pdf

If included in the DaVinci main sequence, a .dot file will be created for every candidate at the input TES location(s). The MCTools/BkgTreePlotter package is required and the configuration is:

from Configurables import DotCreator
DaVinci().appendToMainSequence ( [ DotCreator(Inputs = [ "Phys/MyTau23MuCandidates/Particles" ] ) ] )

for an apropriate TES location. The .dot files can be converted to .pdf with the shell script in the package: ./postprocessing.sh will process all .dot files in the current working directory.

The output should look somehow like this:

2812047.36542.0.dot.png

Usage recommendation

I recommend not to create thousands of plots to look at them (dull work and often inconclusive). Either cut very tight on your BDT / neural network until you're left with O(10) events or create a short list of run&event numbers from your ntuple (I assume that you already have ntuples, so let's start from there) and then process these events:

from Configurables import LoKi__ODINFilter
odin = LoKi__ODINFilter (
    'ODINfilter' ,
    Code       =  ' odin_runevts (  the_list ) ' ,
    Preambulo = [
    "from LoKiHlt.functions  import *" ,
    "from LoKiHlt.decorators import *" ,
    "the_list = runevt_lst ( [RunEvt(112290, 888056458), RunEvt(112290,
891370819)] )" ])
DaVinci().EventPreFilters = [odin]

options

DotCreator.NoFragmentation
(enabled by default) suppresses string fragmentation, so you won't see gazillions of fragmentation particles. For tagging studies, you might want to change this.

Feedback

Please send feedback to Paul.Seyfert-at-mib.infn.it. Especially the following items are of interest:

  • at the moment, each candidate receives their own diagram. (from the filename you will
    see that the candidates are from the same event)
    → feedback welcome: should they go to the same diagram? how to highlight which
    tracks belong to which candidate?
  • when you reconstruct B 0s → D s (KKπ)π, the plot wonít distinguish the bachelor pion from
    the D daughter pion.
    → feedback welcome: is this needed? suggestions how to best visualise
  • I didnít test how the code reacts when encountering a π 0 candidate and I know too little
    about MC association of neutral clusters
    → feedback welcome: test case
  • At the moment the list of MCVertexTypes which are ignored is hard coded. There is no
    cut on the z position of the MCVertex
    → feedback welcome: is this needed to be configurable?
-- PaulSeyfert - 2015-05-11
Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng 2812047.36542.0.dot.png r1 manage 53.9 K 2015-05-11 - 16:06 PaulSeyfert an example (with a custom font)
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Topic revision: r2 - 2016-02-01 - PaulSeyfert
 
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