KlongDecayReconstructionExample.py

#!/usr/bin/env python3
 
 
 
 
 
import basf2
import modularAnalysis as ma
from stdCharged import stdMu
from stdKlongs import stdKlongs
import variables.collections as vc
import variables.utils as vu
from variables import variables
from vertex import TagV, kFit
 
 
main = basf2.create_path()
 
ma.inputMdstList([basf2.find_file('B02JpsiKL_Jpsi2mumu.root', 'examples', False)], path=main)
 
# Show progress of processing
main.add_module('ProgressBar')
 
stdMu('loose', path=main)
stdKlongs('allklm', path=main)
 
ma.reconstructDecay('J/psi:mumu -> mu-:loose mu+:loose', cut='3.08 < M < 3.12  and 1.45 < useCMSFrame(p) < 1.95', path=main)
 
pcalc = basf2.register_module('KlongMomentumCalculatorExpert')
pcalc.set_name('KlongMomentumCalculatorExpert_' + 'B0 -> J/psi:mumu K_L0:allklm')
pcalc.param('decayString', 'B0 -> J/psi:mumu K_L0:allklm')
pcalc.param('writeOut', False)
pcalc.param('recoList', "_reco")
main.add_module(pcalc)
 
rmake = basf2.register_module('KlongDecayReconstructorExpert')
rmake.set_name('KlongDecayReconstructorExpert_' + 'B0 -> J/psi:mumu K_L0:allklm')
rmake.param('decayString', 'B0 -> J/psi:mumu K_L0:allklm')
rmake.param('cut', 'M > 0')
rmake.param('decayMode', 0)
rmake.param('writeOut', False)
rmake.param('recoList', "_reco")
main.add_module(rmake)
 
ma.buildRestOfEvent('B0', path=main)
ma.matchMCTruth('B0', path=main)
 
kFit(list_name='B0', conf_level=-1, fit_type='vertex', constraint='iptube',
     decay_string='B0 -> [J/psi -> ^mu- ^mu+] K_L0',
     daughtersUpdate=False,  # if true, kinematics of J/psi -> mu- mu+ will be updated
     path=main)
 
# The vertex fit changes the kinematics of the B-meson.
# Re-calculate the kinematics with the same method
ma.updateKlongKinematicsExpert('B0', path=main)
 
TagV('B0', constraintType='tube', confidenceLevel=0.0001, path=main)
 
commonVariables = vc.inv_mass + vc.mc_truth
commonVariables += vc.kinematics + vc.mc_kinematics
commonVariables += vc.vertex + vc.mc_vertex
 
variableList = [var for var in commonVariables]
variableList += vc.deltae_mbc + vc.tag_vertex + vc.mc_tag_vertex + vc.reco_stats
variableList += vu.create_aliases(commonVariables, 'daughter(0, {variable})', 'Jpsi')
variableList += vu.create_aliases(commonVariables, 'daughter(1, {variable})', 'KL0')
variableList += vu.create_aliases(vc.kinematics, 'useCMSFrame({variable})', 'CMS')
variableList += vu.create_aliases(vc.kinematics, 'daughter(0, useCMSFrame({variable}))', 'Jpsi_CMS')
variableList += vu.create_aliases(vc.kinematics, 'daughter(1, useCMSFrame({variable}))', 'KL0_CMS')
variables.addAlias('dmID', 'extraInfo(decayModeID)')
variableList += ['dmID']
 
ma.variablesToNtuple('B0', variables=variableList, filename="Reconstruct_jpsi_kl_example.root", treename='tree', path=main)
 
# Process all modules added to the main path
basf2.process(main)
 
# Print out the summary
print(basf2.statistics)