reconstructMCDecay.py

#!/usr/bin/env python3
 
# Doxygen should skip this script
# @cond
 
"""
An example script to find a specific decay chain at MC level.
"""
 
__authors__ = "Yo Sato"
 
import basf2
from ROOT import Belle2
from modularAnalysis import inputMdst, fillParticleListFromMC, variablesToNtuple, reconstructMCDecay, fillParticleList
from variables import variables as vm  # shorthand for the variable manager instance
 
basf2.set_log_level(basf2.LogLevel.DEBUG)
 
mypath = basf2.create_path()
testinput = Belle2.FileSystem.findFile('analysis/tests/mdst.root')
inputMdst("default", testinput, path=mypath)
 
fillParticleListFromMC('K+:MC', 'mcPrimary', path=mypath)
fillParticleListFromMC('pi+:MC', 'mcPrimary', path=mypath)
fillParticleListFromMC('e+:MC', 'mcPrimary', path=mypath)
fillParticleListFromMC('nu_e:MC', 'mcPrimary', path=mypath)
fillParticleListFromMC('gamma:MC', 'mcPrimary', path=mypath)
 
reconstructMCDecay('pi0:gg =direct=> gamma:MC gamma:MC', '', path=mypath)
reconstructMCDecay(
    'B+:DstENu =direct=> [anti-D*0 =direct=> [anti-D0 =direct=> K+:MC pi-:MC pi0:gg] pi0:gg ] e+:MC nu_e:MC ',
    '',
    path=mypath)
 
 
# One can directly reconstruct pi0:gg in same decay string as following.
# But in this case, one has to write sub-decay only once. Otherwise same particles are registered twice.
#
# reconstructMCDecay(
#     'B+:DstENu =direct=>\
# [anti-D*0 =direct=> [anti-D0 =direct=> K+:MC pi-:MC [pi0:gg =direct=> gamma:MC gamma:MC]] pi0:gg ]\
# e+:MC nu_e:MC ',
#     '',
#     path=mypath)
 
 
interesting_variables = ['isSignal', "Mbc", "deltaE", "mcErrors"]
 
vm.printAliases()
 
variablesToNtuple("B+:DstENu", interesting_variables, path=mypath)
 
basf2.process(mypath)
print(basf2.statistics)
 
# @endcond