SCT parametric simulation

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= SctParSim (WIP) =
+
= How to run =
−
A parametric simulation is a tool to receive a detector response without detailed description of interaction of particles with matter.
+
  
−
Implemented detector subsystems:
+
Login to stark or proxima machine.
−
* drift chamber
+
<pre>
−
* FARICH PID system
+
ssh stark -X
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* calorimeter
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setupSCTAU; asetup SCTauSim,master,latest
−
* muon system
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mkdir workarea
 +
cd workarea
 +
mkdir run
 +
cd run
 +
cp /home/razuvaev/public/misc/pi_ms_f1_mppc2_px3_d200_mla4_graph2d.root .
 +
cp /home/razuvaev/public/misc/g4beamline_pi_plus_100k_parse.root .
 +
cp /home/razuvaev/public/misc/g4beamline_mu_plus_100k_parse.root .
 +
ctaurun SctParSimAlg/sctparsim_test_particle_gun.py
 +
</pre>
  
−
The parametric simulation yields the detector response in the SCT EDM format thus allowing to analyze its result in the same manner as the result of the full simulation.
+
= Configure example =
  
−
== Detector configuration ==
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There are some examples to run the parametric simulation
−
 
+
−
The detector parameters can be changed in the run script (see Configuration section).
+
−
The detector parameters and their default values can be viewed here.
+
−
 
+
−
=== SctParSimAlg ===
+
 
{| class="wikitable"
 
{| class="wikitable"
 
|-  
 
|-  
−
! Name to change parameter
+
! Using tools
−
! Description
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! Link
−
! Default value
+
 
|-
 
|-
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| B
+
| Read from a ROOT-file, write to a ROOT-file
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| Detector magnetic field
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| [https://git.inp.nsk.su/sctau/aurora/-/blob/master/Simulation/SctParSimAlg/jobOptions/sctparsim_test_read.py sctparsim_test_read.py]
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| 1.5
+
 
|-
 
|-
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| mostProbMass
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| Generate using the particle gun, write to a ROOT-file
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| The mass of most probable particle
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| [https://git.inp.nsk.su/sctau/aurora/-/blob/master/Simulation/SctParSimAlg/jobOptions/sctparsim_test_particle_gun.py sctparsim_test_particle_gun.py]
−
| 0.13957
+
−
|}
+
−
 
+
−
=== TrackSystemTool ===
+
−
{| class="wikitable"
+
−
|-  
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−
! Name to change paramater
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−
! Description
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−
! Default value
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|-
 
|-
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| trackRhoMin
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| Generate using <code>EvtGen</code>, write to a ROOT-file
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| Inner radius of barrel tracker, m       
+
| [https://git.inp.nsk.su/sctau/aurora/-/blob/master/Simulation/SctParSimAlg/jobOptions/sctparsim_test_evtgen.py sctparsim_test_evtgen.py]
−
| 0.1
+
 
|-
 
|-
−
| trackRhoMax             
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| Generate using <code>EvtGen</code>, use the analysis tool
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| Outer radius of barrel tracker, m       
+
| [https://git.inp.nsk.su/sctau/aurora/-/blob/master/Simulation/SctParSimAlg/jobOptions/sct_run_test_analisis.py sct_run_test_analisis.py]
−
| 0.8
+
−
|-
+
−
| trackZMin               
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−
| Inner z coordinate of endcup tracker, m 
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−
| 0 
+
−
|-
+
−
| trackZMax               
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−
| Outer z coordinate of endcup tracker, m 
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−
| 1 
+
−
|-
+
−
| trackMinPt             
+
−
| Minimum momentum, GeV                   
+
−
|0.05
+
−
|-
+
−
| trackPtProb             
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−
| Registration probabilities for different momentum, {GeV, prob}
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| {{0.1, 0.8}, {0.3, 0.9}, {1, 0.95), {10, 0.99}}
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−
|-
+
−
| trackRadLen             
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−
| Radiation length in the track system, m 
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| 187
+
−
|-
+
−
| trackResParPT           
+
−
| Parameterizaton parameters for xy projection
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−
| 0.00212
+
−
|-
+
−
| trackResParPZ           
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−
| Parameterization parameters for z projection
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| {0.001281, 0.00308}
+
−
|-
+
−
| trackLayerAx           
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| The radius of layers anf the location radius of the anod layers, mm
+
−
| {{6.306, 217.306}, {6.644, 227.1}, {7.165, 246.906}, {6.564, 341.938}, {6.794, 352.06}, {7.14, 371.992}, {7.388, 382.95}, {6.651, 467.57}, {6.823, 477.718}, {6.968, 488.097}, {7.12, 498.701}, {7.274, 509.535}, {6.768, 636.322}, {6.898, 646.501}, {7.007, 656.957}, {7.121, 667.581}, {6.791, 750.730}, {6.902, 761.027}, {6.995, 771.472}, {7.091, 782.061}}
+
−
|-
+
−
| trackLayerSt           
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| The radius of layers and the location radius of the stereo layers, mm
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−
| {{6.473, 280.136}, {6.747, 290.136}, {7.182, 310.863}, {7.486, 321.938}, {6.603, 405.941}, {6.799, 416.04}, {7.104, 436.741}, {7.314, 447.606}, {6.741, 533.35}, {6.859, 543.615}, {7.026, 554.088, {7.161, 564.762}, {6.778, 584.801}, {6.919, 595.108}, {7.039, 605.606}, {7.163, 6169.289}, {6.746, 689.948}, {6.865, 700.185}, {7.041, 720.09}, {7.165, 730.775}}
+
 
|}
 
|}
  
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=== FARICHSystemTool ===
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== Event generation ==
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{| class="wikitable"
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−
|-
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−
! Name to change paramater
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−
! Description                         
+
−
! Default value     
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−
|-
+
−
| farichRhoMin           
+
−
| Inner radius of barrel FARICH system, m         
+
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| 0.82   
+
−
|-
+
−
| farichRhoMax           
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−
| Outer radius of barrel FARICH system, m         
+
−
| 0.9   
+
−
|-
+
−
| farichZMin             
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−
| Inner z coordinate of endcup FARICH system, m   
+
−
| 1.02   
+
−
|-
+
−
| farichZMax             
+
−
| Outer z coordinate of encup FARICH system, m   
+
−
| 1.273 
+
−
|-
+
−
| farichHoleR             
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| Hole radius of FARICH system                   
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| 0.3   
+
−
|-
+
−
| parSimFarichFileName   
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−
| The path to the file with response histograms of FARICH
+
−
| ./pi_ms_f1_mppc2_px3_d200_mla4_graph2d.root
+
−
|}
+
  
−
=== CaloSystemTool ===
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The "Event generation" block may contain other options: to read a ROOT file, to generate using the particle gun tool and to generate using EvtGen.
−
{| class="wikitable"
+
−
|-
+
−
! Name to change paramater
+
−
! Description                         
+
−
! Default value     
+
−
|-
+
−
| caloRhoMin             
+
−
| Inner radius of barrel calorimeter, m           
+
−
| 1.09   
+
−
|-
+
−
| caloRhoMax             
+
−
| Outer radius of barrel calorimeter, m           
+
−
| 1.55   
+
−
|-
+
−
| caloZMin               
+
−
| Inner z coordinate of endcup calorimeter, m     
+
−
| 1.293 
+
−
|-
+
−
| caloZMax               
+
−
| Outer z coordinate of endcup calorimeter, m     
+
−
| 1.86 
+
−
|-
+
−
| caloCosthmax           
+
−
| Maximum cosine                                 
+
−
| 0.9   
+
−
|-
+
−
| caloClSize             
+
−
| Calorimeter cluster size, m                     
+
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| 0.045 
+
−
|-
+
−
| caloClSizeEGamma       
+
−
| Calorimeter cluster size for gamma, m           
+
−
| 0.15 
+
−
|-
+
−
| caloEMinBarrel         
+
−
| Minimal energy, GeV                             
+
−
| 0.015 
+
−
|-
+
−
| caloEMinEndcup         
+
−
| Minimal energy, GeV                             
+
−
| 0.015 
+
−
|-
+
−
| caloResPar             
+
−
| Parameterization parameters                     
+
−
| {1.34e-2, 0.066e-2, 0.0, 0.82e-2}
+
−
|}
+
  
−
=== MuonSystemTool ===
+
=== Podio input ===
−
{| class="wikitable"
+
−
|-
+
−
! Name to change paramater
+
−
! Description                         
+
−
! Default value     
+
−
|-
+
−
| muonRhoMin             
+
−
| Inner radius of barrel muon system, m           
+
−
| 1.87   
+
−
|-
+
−
| muonRhoMax             
+
−
| Outer radius of barrel muon system, m           
+
−
| 2.15   
+
−
|-
+
−
| muonZMin               
+
−
| Inner z coordinate of endcup muon system, m     
+
−
| 1.88   
+
−
|-
+
−
| muonZMax               
+
−
| Outer z coordinate of endcup muon system, m     
+
−
| 2.16   
+
−
|-
+
−
| parSimMuonFileNameMu   
+
−
| The path to the file with response histograms of muon system (muon)
+
−
| ./g4beamline_mu_plus_100k_parse.root
+
−
|-
+
−
| parSimMuonFileNamePi   
+
−
| The path to the file with response histograms of muon system (pion)
+
−
| ./g4beamline_pi_plus_100k_parse.root
+
−
|}
+
  
 +
It is possible to read the particle parameters from a ROOT file.
  
−
== Parameterization (WIP) ==
+
You have to import the library
−
=== Drift chamber (WIP) ===
+
<pre>
 +
from Configurables import PodioInput
 +
</pre>
  
−
=== FARICH PID system ===
+
and to create the algorithm instance
 +
<pre>
 +
podioevent = ScTauDataSvc("EventDataSvc", input="fileName.root")
 +
podioinput = PodioInput("PodioReader", OutputLevel=INFO, collections=['allGenParticles'])
 +
</pre>
  
−
The FARICH PID system works using the results of the full GEANT4 simulation. The system output is the particle speed and number of photons.
+
The reading algorithm has the following parameters:
 +
* input - an input file name
 +
* collections - a name of a branch with MC particles
  
−
<gallery>
+
=== Particle gun ===
−
File:Farich_res.png|The dependence of the particle β factor on the momentum in the FARICH PID system
+
  
−
File:Farich_param.png|The dependence of the number of photoelectron on the βγ factor in the FARICH PID system for different angles (black - 10, red - 30, green - 45)
+
To use the particle gun algorithm, it is necessary to import the following libraries
−
</gallery>
+
<pre>
 +
from Configurables import ParticleGun
 +
from Configurables import GenAlg
 +
from Configurables import HepMCToEDMConverter
 +
from Configurables import HepMCFileWriter
  
−
=== Calorimeter (WIP) ===
+
from Configurables import Gaudi__ParticlePropertySvc
 +
from PathResolver import PathResolver
 +
</pre>
  
 +
and to write the following strings
 +
<pre>
 +
particlePropertySvc = Gaudi__ParticlePropertySvc(
 +
    "ParticlePropertySvc",
 +
    ParticlePropertiesFile=PathResolver.FindDataFile('GenParticleData/ParticleTable.txt')
 +
)
  
−
=== Muon system ===
+
from math import pi
−
The muon system works using the results of a reconducted stand-alone simulation on G4BeamLine. The system is a cylinder of eight absorber and sensitive polystyrene layers. The absorber is iron.
+
guntool = ParticleGun("PdgCodes", PdgCodes=[211])
 +
guntool.OutputLevel=DEBUG
  
−
<gallery>
+
guntool.MomentumMin = 0 * units.MeV
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File:muon.png|The probability distribution for muons and pions to reach a certain layer in the muon system
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guntool.MomentumMax = 4 * units.GeV
−
</gallery>
+
  
−
= Configuration =
+
guntool.ThetaMin = 0 * units.rad
 +
guntool.ThetaMax = pi * units.rad
  
−
<pre>
+
guntool.PhiMin = 0 * units.rad
−
from Configurables import ApplicationMgr
+
guntool.PhiMax = 2 * pi * units.rad
  
−
from Gaudi.Configuration import *
+
gun = GenAlg("ParticleGun", SignalProvider=guntool)
−
from Configurables import GenAlg, EvtGenInterface
+
gun.hepmc.Path = "hepmc"
−
from Configurables import HepMCToEDMConverter
+
−
from Configurables import ScTauDataSvc
+
  
−
from Configurables import PodioOutput
+
writer = HepMCFileWriter("HepMCFileWriter")
 +
writer.hepmc.Path="hepmc"
  
−
from Configurables import SctParSimAlg
+
hepmc_converter = HepMCToEDMConverter("Converter")
−
from Configurables import EventLoader
+
hepmc_converter.hepmc.Path="hepmc"
−
from Configurables import NtupleAlg, NTupleSvc
+
hepmc_converter.genparticles.Path="allGenParticles"
−
from Configurables import ParticleCombinerAlg
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hepmc_converter.genvertices.Path="allGenVertices"
 +
</pre>
  
−
from Configurables import Gaudi__ParticlePropertySvc
+
Some parameters can be changed:
−
from PathResolver import PathResolver
+
* PdgCodes - a list containing particles PDG codes to generate
 +
* MomentumMin - a minimum particle momentum
 +
* MomentumMax - a maximum particle momentum
 +
* ThetaMin - a minimum theta angle
 +
* ThetaMax - a maximum theta angle
 +
* PhiMin - a minimum phi angle
 +
* PhiMax - a maximum phi angle
  
−
ofile = 'sctparsim_out.root' # name of output file
+
=== EvtGen ===
−
eventNumber = 50000 # number of events
+
  
−
############################
+
More information about EvtGen is [https://ctd.inp.nsk.su/wiki/index.php/Event_generators here].
−
####  Event generation  ####
+
−
############################
+
−
podioevent = ScTauDataSvc("EventDataSvc")
+
  
−
# Particle service
+
<code>EvtGen</code> interface has the following parameters:
−
particlePropertySvc = Gaudi__ParticlePropertySvc(
+
* <code>dec</code> - EvtGen users decay file. It can be one of the included in Aurora files or absolute path to your own decay file. Inclusive MC generation does not require user decay file
−
    "ParticlePropertySvc",
+
* <code>root</code> - root particle for EvtGen. <code>vpho</code> (virtual photon) should be used for non-resonant processes
−
    ParticlePropertiesFile=PathResolver.FindDataFile('GenParticleData/ParticleTable.txt')
+
** Acceptable root particles: <code>vpho</code>, <code>J/psi</code>, <code>psi(2S)</code>, <code>psi(3770)</code>, <code>psi(4040)</code>, <code>psi(4160)</code>, <code>psi(4415)</code>. For more details see Generation/GenTools/GenWrappers/python/EvtGenTools.py in Aurora.
−
)
+
* <code>ecms</code> - center-of-mass energy (mass of the root particle). The parameter <code>ecms</code> must be set for virtual photon while for other root particles (<math>J/\psi</math>, <math>\psi(2S)</math>, ...) this parameter is optional. Mean mass of the root particle is adopted if <code>ecms</code> is omitted.
 +
* <code>nevt</code> - number if events to be gnerated
 +
* <code>ip</code> - uniform 3D smearing (in mm) for the primary vertex
 +
* <code>ofile</code> - output file name
 +
One can change these parameters to change behaviour of EvtGen and to produce arbitrary MC sample.
  
−
# EvtGen
+
== SctParSim ==
−
evtgen = EvtGenInterface('SignalProvider')
+
−
#evtgen.userdec = "./mydec.dec"
+
−
#evtgen.rootParticle = "J/psi"
+
  
−
gen = GenAlg('EvtGenAlg', SignalProvider=evtgen)
+
To run the parametric simulation, the script has to have two lines:
−
gen.hepmc.Path = 'hepmc'
+
<pre>
 +
from Configurables import SctParSimAlg
 +
sct_alg = SctParSimAlg('SctAlg')
 +
</pre>
  
−
# HepMC3 to PODIO
+
To change some detector parameters, write strings of the following structure
−
edm = HepMCToEDMConverter("Converter")
+
<pre>
−
edm.hepmc.Path=gen.hepmc.Path
+
sct_alg.detectorSubsystemName.parameter = mean
−
edm.genparticles.Path="allGenParticles"
+
</pre>
−
edm.genvertices.Path="allGenVertices"
+
  
−
############################
+
The full parameters list is [https://ctd.inp.nsk.su/wiki/index.php/SctParSim_(Aurora) here].
−
# SctParSim
+
−
############################
+
−
sct_alg = SctParSimAlg('SctAlg')
+
−
#sct_alg.CaloSystemTool.caloClSizeEGamma = 0.2 # Example how to change a subsystem parameter
+
  
−
############################
+
== Analysis ==
−
# Podio output
+
−
############################
+
−
out = PodioOutput('out', filename=ofile)
+
−
out.outputCommands = ["keep *"]
+
  
−
############################       
+
The analysis tool has the following parameters:
−
# Analisis                         
+
* EventLoader
−
############################
+
** pcl.Path - a branch (in the input ROOT-file) for reading
 +
** plists - a partilce list for further analisis. if it is necessary to consider not only positive, but also negative particles, the label "сс" is used. For example <code>[['K+ cc'], ['pi+ cc']]</code>. Also it is possible to write a kinematic constraint; for example <code>[['K+ cc', 'p > 0.5'], ['pi+ cc']]</code>  (kaons don't have the momentum less then 0.5 GeV)
  
−
evlo = EventLoader('EvtLoader')
+
* ParticleCombinerAlg
−
evlo.pcl.Path = 'Particles' # Branch (in the input ROOT-file) for reading
+
** decStr - an investigated decay
−
evlo.pListMap.Path = 'Lists1'
+
** cutStr - a selection criteria
−
evlo.plists = [['gamma']] # Partilce list for further analisis
+
** selfConj - if neutral particle <code>True</code>, else <code>False</code>
  
−
# Select particle combinations     
+
* NtupleAlg
−
cmbr = ParticleCombinerAlg('Cmbr',
+
** vars - a list contains the particle parameters to write an output file. A particle in the decay string can be selected using the "^" symbol. If a decay isn't written (<code>''</code>), the information about parameters will be about a parent particle.
−
    decStr = 'pi0 -> gamma gamma', # Investigated decay
+
−
    cutStr = 'E > 0.5', # Selection criteria
+
−
    selfConj = True # if neutral particle True, else False
+
−
)
+
  
−
cmbr.pListMapI = evlo.pListMap.Path
+
More information about the analysis tool is [https://ctd.inp.nsk.su/wiki/index.php/Use_Analysis_package here].
−
cmbr.pListMapO.Path = 'Lists2'
+
  
−
# Select variables to save to n-tuple
+
== Podio output ==
−
tupl = NtupleAlg('piTuple')
+
−
tupl.listName = 'pi0'
+
−
tupl.fileName = 'scttuple/tup'
+
  
−
# List contains the particle parametes to write an output file
+
It is possible to write the particle parameters to a ROOT file.
−
tupl.vars = [['px_mc', 'py_mc', 'pz_mc', 'E', 'pi0 -> ^gamma ^gamma'],
+
−
    ['M', ''],
+
−
]
+
  
−
tupl.pListMapI.Path = cmbr.pListMapO.Path
+
You have to import the library
−
NTupleSvc(Output = ["scttuple DATAFILE='tup.root' OPT='NEW' TYP='ROOT'"])
+
<pre>
 +
from Configurables import PodioOutput
 +
</pre>
  
−
options= {
+
and to create the algorithm instance
−
    'TopAlg' : [gen, edm, sct_alg, evlo, cmbr, tupl],
+
<pre>
−
    'EvtSel' : 'NONE',
+
out = PodioOutput('out', filename=ofile)
−
    'ExtSvc' : [particlePropertySvc, podioevent],
+
out.outputCommands = ["keep *"]
−
    'EvtMax' : eventNumber,
+
−
    'StatusCodeCheck' : True,
+
−
    'AuditAlgorithms' : True,
+
−
    'AuditTools'      : True,
+
−
    'AuditServices'  : True,
+
−
    'OutputLevel'    : INFO,
+
−
    'HistogramPersistency' : 'ROOT',
+
−
}
+
−
 
+
−
ApplicationMgr(**options)
+
 
</pre>
 
</pre>
  
−
More examples are shown in [https://git.inp.nsk.su/sctau/aurora/-/blob/master/Simulation/SctParSimAlg/jobOptions jobOptions]
+
The reading algorithm has the parameter: filename - an output file name.
 +
 
 +
== Running algorithm ==
 +
 
 +
Some necessary parametrs to run the algorithms:
 +
* TopAlg - a list of the using algorithms
 +
* EvtMax - a number of events

Latest revision as of 13:34, 24 November 2021

Contents

[edit] How to run

Login to stark or proxima machine. 

ssh stark -X
setupSCTAU; asetup SCTauSim,master,latest
mkdir workarea
cd workarea
mkdir run
cd run
cp /home/razuvaev/public/misc/pi_ms_f1_mppc2_px3_d200_mla4_graph2d.root .
cp /home/razuvaev/public/misc/g4beamline_pi_plus_100k_parse.root .
cp /home/razuvaev/public/misc/g4beamline_mu_plus_100k_parse.root .
ctaurun SctParSimAlg/sctparsim_test_particle_gun.py

[edit] Configure example

There are some examples to run the parametric simulation

Using tools Link
Read from a ROOT-file, write to a ROOT-file sctparsim_test_read.py
Generate using the particle gun, write to a ROOT-file sctparsim_test_particle_gun.py
Generate using EvtGen, write to a ROOT-file sctparsim_test_evtgen.py
Generate using EvtGen, use the analysis tool sct_run_test_analisis.py

[edit] Event generation

The "Event generation" block may contain other options: to read a ROOT file, to generate using the particle gun tool and to generate using EvtGen.

[edit] Podio input

It is possible to read the particle parameters from a ROOT file.

You have to import the library 

from Configurables import PodioInput

and to create the algorithm instance 

podioevent = ScTauDataSvc("EventDataSvc", input="fileName.root")
podioinput = PodioInput("PodioReader", OutputLevel=INFO, collections=['allGenParticles'])

The reading algorithm has the following parameters:

  • input - an input file name
  • collections - a name of a branch with MC particles

[edit] Particle gun

To use the particle gun algorithm, it is necessary to import the following libraries 

from Configurables import ParticleGun
from Configurables import GenAlg
from Configurables import HepMCToEDMConverter
from Configurables import HepMCFileWriter

from Configurables import Gaudi__ParticlePropertySvc
from PathResolver import PathResolver

and to write the following strings 

particlePropertySvc = Gaudi__ParticlePropertySvc(
    "ParticlePropertySvc",
    ParticlePropertiesFile=PathResolver.FindDataFile('GenParticleData/ParticleTable.txt')
)

from math import pi
guntool = ParticleGun("PdgCodes", PdgCodes=[211])
guntool.OutputLevel=DEBUG

guntool.MomentumMin = 0 * units.MeV 
guntool.MomentumMax = 4 * units.GeV

guntool.ThetaMin = 0 * units.rad 
guntool.ThetaMax = pi * units.rad 

guntool.PhiMin = 0 * units.rad
guntool.PhiMax = 2 * pi * units.rad 

gun = GenAlg("ParticleGun", SignalProvider=guntool)
gun.hepmc.Path = "hepmc"

writer = HepMCFileWriter("HepMCFileWriter")
writer.hepmc.Path="hepmc"

hepmc_converter = HepMCToEDMConverter("Converter")
hepmc_converter.hepmc.Path="hepmc"
hepmc_converter.genparticles.Path="allGenParticles"
hepmc_converter.genvertices.Path="allGenVertices"

Some parameters can be changed:

  • PdgCodes - a list containing particles PDG codes to generate
  • MomentumMin - a minimum particle momentum
  • MomentumMax - a maximum particle momentum
  • ThetaMin - a minimum theta angle
  • ThetaMax - a maximum theta angle
  • PhiMin - a minimum phi angle
  • PhiMax - a maximum phi angle

[edit] EvtGen

More information about EvtGen is here.

EvtGen interface has the following parameters:

  • dec - EvtGen users decay file. It can be one of the included in Aurora files or absolute path to your own decay file. Inclusive MC generation does not require user decay file
  • root - root particle for EvtGen. vpho (virtual photon) should be used for non-resonant processes
    • Acceptable root particles: vpho, J/psi, psi(2S), psi(3770), psi(4040), psi(4160), psi(4415). For more details see Generation/GenTools/GenWrappers/python/EvtGenTools.py in Aurora.
  • ecms - center-of-mass energy (mass of the root particle). The parameter ecms must be set for virtual photon while for other root particles (J/\psi, \psi(2S), ...) this parameter is optional. Mean mass of the root particle is adopted if ecms is omitted.
  • nevt - number if events to be gnerated
  • ip - uniform 3D smearing (in mm) for the primary vertex
  • ofile - output file name

One can change these parameters to change behaviour of EvtGen and to produce arbitrary MC sample.

[edit] SctParSim

To run the parametric simulation, the script has to have two lines: 

from Configurables import SctParSimAlg
sct_alg = SctParSimAlg('SctAlg')

To change some detector parameters, write strings of the following structure 

sct_alg.detectorSubsystemName.parameter = mean

The full parameters list is here.

[edit] Analysis

The analysis tool has the following parameters:

  • EventLoader
    • pcl.Path - a branch (in the input ROOT-file) for reading
    • plists - a partilce list for further analisis. if it is necessary to consider not only positive, but also negative particles, the label "сс" is used. For example [['K+ cc'], ['pi+ cc']]. Also it is possible to write a kinematic constraint; for example [['K+ cc', 'p > 0.5'], ['pi+ cc']] (kaons don't have the momentum less then 0.5 GeV)
  • ParticleCombinerAlg
    • decStr - an investigated decay
    • cutStr - a selection criteria
    • selfConj - if neutral particle True, else False
  • NtupleAlg
    • vars - a list contains the particle parameters to write an output file. A particle in the decay string can be selected using the "^" symbol. If a decay isn't written (), the information about parameters will be about a parent particle.

More information about the analysis tool is here.

[edit] Podio output

It is possible to write the particle parameters to a ROOT file.

You have to import the library 

from Configurables import PodioOutput

and to create the algorithm instance 

out = PodioOutput('out', filename=ofile)
out.outputCommands = ["keep *"]

The reading algorithm has the parameter: filename - an output file name.

[edit] Running algorithm

Some necessary parametrs to run the algorithms:

  • TopAlg - a list of the using algorithms
  • EvtMax - a number of events
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