##########################################################################
# basf2 (Belle II Analysis Software Framework) #
# Author: The Belle II Collaboration #
# #
# See git log for contributors and copyright holders. #
# This file is licensed under LGPL-3.0, see LICENSE.md. #
##########################################################################
'''
This module contains convenience functions to setup most commonly used physics
generators correctly with their default settings. More information can be found
in `BELLE2-NOTE-PH-2015-006`_
.. _BELLE2-NOTE-PH-2015-006: https://docs.belle2.org/record/282
'''
import basf2 as b2
import pdg
[docs]def get_default_decayfile():
"""Return the default DECAY.dec for Belle2"""
return b2.find_file("decfiles/dec/DECAY_BELLE2.DEC")
[docs]def add_generator_preselection(
path,
emptypath,
nChargedMin=0,
nChargedMax=999,
MinChargedP=-1.0,
MinChargedPt=-1.0,
MinChargedTheta=0.0,
MaxChargedTheta=180.0,
nPhotonMin=0,
nPhotonMax=999,
MinPhotonEnergy=-1,
MinPhotonTheta=0.0,
MaxPhotonTheta=180.0,
applyInCMS=False,
stableParticles=False):
"""
Adds generator preselection.
Should be added to the path after the generator.add_abc_generator but before simulation.add_simulation modules
It uses all particles from the event generator (i.e. primary, non-virtual, non-initial particles).
It checks if the required conditions are fulfilled.
If not, the events are given to the emptypath.
The main use case is a reduction of simulation time.
Note that you have to multiply the generated cross section by the retention fraction of the preselection.
Parameters:
path (basf2.Path): path where the generator should be added
emptypath (basf2.Path): path where the skipped events are given to
nChargedMin (int): minimum number of charged particles
nChargedMax (int): maximum number of charged particles
MinChargedP (float): minimum charged momentum [GeV]
MinChargedPt (float): minimum charged transverse momentum (pt) [GeV]
MinChargedTheta (float): minimum polar angle of charged particle [deg]
MaxChargedTheta (float): maximum polar angle of charged particle [deg]
nPhotonMin (int): minimum number of photons
nPhotonMax (int): maximum number of photons
MinPhotonEnergy (float): minimum photon energy [GeV]
MinPhotonTheta (float): minimum polar angle of photon [deg]
MaxPhotonTheta (float): maximum polar angle of photon [deg]
applyInCMS (bool): if true apply the P,Pt,theta, and energy cuts in the center of mass frame
stableParticles (bool): if true apply the selection criteria for stable particles in the generator
"""
generatorpreselection = path.add_module('GeneratorPreselection',
nChargedMin=nChargedMin,
nChargedMax=nChargedMax,
MinChargedP=MinChargedP,
MinChargedPt=MinChargedPt,
MinChargedTheta=MinChargedTheta,
MaxChargedTheta=MaxChargedTheta,
nPhotonMin=nPhotonMin,
nPhotonMax=nPhotonMax,
MinPhotonEnergy=MinPhotonEnergy,
MinPhotonTheta=MinPhotonTheta,
MaxPhotonTheta=MaxPhotonTheta,
stableParticles=stableParticles
)
# empty path for unwanted events
generatorpreselection.if_value('<11', emptypath)
[docs]def add_aafh_generator(
path,
finalstate='',
preselection=False,
enableTauDecays=True,
minmass=0.5,
subweights=[],
maxsubweight=1,
maxfinalweight=3.0,
eventType=''):
"""
Add the default two photon generator for four fermion final states
Parameters:
path (basf2.Path): path where the generator should be added
finalstate (str): either "e+e-e+e-", "e+e-mu+mu-", "e+e-tau+tau-", "mu+mu-mu+mu-" or "mu+mu-tau+tau-"
preselection (bool): if True, select events with at least one medium pt particle in the CDC acceptance
enableTauDecays (bool): if True, allow tau leptons to decay (using EvtGen)
minmass (float): minimum invariant mass
subweights (list(float)): list of four or eight values (first four are interpreted as WAP, rest as WBP)
which specify the relative weights for each of the four sub generators
maxsubweight (float): maximum expected subgenerator weight for rejection scheme
maxfinalweight (float): maximum expected final weight for rejection scheme
eventType (str) : event type information
"""
if finalstate == 'e+e-e+e-':
aafh_mode = 5
if not subweights: # default subweights are for minmass=0.5
aafh_subgeneratorWeights = [1.0, 7.986e+01, 5.798e+04, 3.898e+05, 1.0, 1.664e+00, 2.812e+00, 7.321e-01]
else:
aafh_subgeneratorWeights = subweights
if abs(minmass - 0.5) > 0.01 and not subweights:
b2.B2WARNING("add_aafh_generator: non default invariant mass cut without updated subweights requested!")
elif finalstate == 'e+e-mu+mu-':
aafh_mode = 3
if not subweights: # default subweights are for minmass=0.5
aafh_subgeneratorWeights = [1.000e+00, 1.520e+01, 3.106e+03, 6.374e+03, 1.000e+00, 1.778e+00, 6.075e+00, 6.512e+00]
else:
aafh_subgeneratorWeights = subweights
if abs(minmass - 0.5) > 0.01 and not subweights:
b2.B2WARNING("add_aafh_generator: non default invariant mass cut without updated subweights requested!")
elif finalstate == 'e+e-tau+tau-':
aafh_mode = 4
minmass = 0
if not subweights:
aafh_subgeneratorWeights = [1.000e+00, 2.214e+00, 1.202e+01, 1.536e+01, 1.000e+00, 1.664e+00, 1.680e+01, 6.934e+00]
else:
aafh_subgeneratorWeights = subweights
if preselection:
b2.B2WARNING(
f"You requested a generator preselection for the final state {finalstate}: "
"please consider to remove it, since the cross section is small.")
elif finalstate == 'mu+mu-mu+mu-':
aafh_mode = 2
minmass = 0
maxsubweight = 3
if not subweights:
aafh_subgeneratorWeights = [0.000e+00, 0.000e+00, 1.000e+00, 3.726e+00, 1.000e+00, 1.778e+00, 1.000e+00, 1.094e+00]
else:
aafh_subgeneratorWeights = subweights
if preselection:
b2.B2WARNING(
f"You requested a generator preselection for the final state {finalstate}: "
"please consider to remove it, since the cross section is small.")
elif finalstate == 'mu+mu-tau+tau-':
aafh_mode = 1
minmass = 0
maxsubweight = 3
if not subweights:
aafh_subgeneratorWeights = [0.000e+00, 0.000e+00, 1.000e+00, 1.715e+00, 1.000e+00, 1.778e+00, 1.000e+00, 6.257e-01]
else:
aafh_subgeneratorWeights = subweights
if preselection:
b2.B2WARNING(
f"You requested a generator preselection for the final state {finalstate}: "
"please consider to remove it, since the cross section is small.")
elif finalstate == 'tau+tau-tau+tau-':
b2.B2FATAL(f"AAFH is not able to generate the {finalstate} final state. Please use KoralW instead.")
else:
b2.B2FATAL(f"add_aafh_generator final state not supported: {finalstate}")
aafh_maxSubgeneratorWeight = maxsubweight
aafh_maxFinalWeight = maxfinalweight
path.add_module(
'AafhInput',
mode=aafh_mode,
rejection=2,
maxSubgeneratorWeight=aafh_maxSubgeneratorWeight,
maxFinalWeight=aafh_maxFinalWeight,
subgeneratorWeights=aafh_subgeneratorWeights,
suppressionLimits=[1e100] * 4,
minMass=minmass,
eventType=eventType,
)
if preselection:
generator_emptypath = b2.create_path()
add_generator_preselection(
path=path,
emptypath=generator_emptypath,
nChargedMin=1,
MinChargedPt=0.1,
MinChargedTheta=17.0,
MaxChargedTheta=150.0)
if 'tau+tau-' in finalstate:
if enableTauDecays:
path.add_module('EvtGenDecay')
else:
b2.B2WARNING("The tau decays will not be generated.")
[docs]def add_kkmc_generator(path, finalstate='', signalconfigfile='', useTauolaBelle=False, tauinputfile='', eventType=''):
"""
Add the default muon pair and tau pair generator KKMC.
For tau decays, TauolaBelle and TauolaBelle2 are available.
Signal events can be produced setting a configuration file. Please notice that the configuration files for
TauolaBelle and TauolaBelle2 has a very different structure (see the examples below generators/examples).
Parameters:
path (basf2.Path): path where the generator should be added
finalstate(str): either "mu-mu+" or "tau-tau+"
signalconfigfile(str): File with configuration of the signal event to generate. It doesn't affect mu-mu+ decays.
useTauolaBelle(bool): If true, tau decay is driven by TauolaBelle. Otherwise TauolaBelle2 is used.
It doesn't affect mu-mu+ decays.
tauinputfile(str) : File to override KK2f_defaults. Only [sometimes] needed when tau decay is driven by TauolaBelle.
eventType (str) : event type information
"""
#: kkmc input file
kkmc_inputfile = b2.find_file('data/generators/kkmc/tauola_bbb.input.dat')
#: kkmc file that will hold cross section and other information
kkmc_logfile = 'kkmc_tautau.txt'
#: kkmc configuration file, should be fine as is
kkmc_config = b2.find_file('data/generators/kkmc/KK2f_defaults.dat')
#: tau config file (empty for generic mu-mu+ and tau-tau+ with TauolaBelle2)
kkmc_tauconfigfile = ''
if finalstate == 'tau+tau-':
b2.B2WARNING("add_kkmc_generator: please set finalstate as 'tau-tau+'. 'tau+tau-' will be deprecated in the future"
" for consistency in the configuration files.")
finalstate = 'tau-tau+'
if finalstate == 'mu+mu-':
b2.B2WARNING("add_kkmc_generator: please set finalstate as 'mu-mu+'. 'mu+mu-' will be deprecated in the future for"
" consistency in the configuration files.")
finalstate = 'mu-mu+'
if finalstate == 'tau-tau+':
if useTauolaBelle:
b2.B2INFO("Generating tau pair events with TauolaBelle")
#: If TauolaBelle, the tau decay must be controlled by Pythia flags
kkmc_inputfile = b2.find_file('data/generators/kkmc/tau.input.dat')
kkmc_tauconfigfile = b2.find_file('data/generators/kkmc/tau_decaytable.dat')
#: Check if there is a signal decfile provided by the user
if not signalconfigfile == '':
b2.B2INFO(f"Using config file defined by user: {signalconfigfile}")
if useTauolaBelle:
kkmc_tauconfigfile = b2.find_file(signalconfigfile)
else:
kkmc_inputfile = b2.find_file(signalconfigfile)
#: Check if there is a tauinputfile to override KK2f_defaults. Only [sometimes] needed when using TauolaBelle.
if not tauinputfile == '':
kkmc_inputfile = b2.find_file(tauinputfile)
elif finalstate == 'mu-mu+':
kkmc_inputfile = b2.find_file('data/generators/kkmc/mu.input.dat')
kkmc_logfile = 'kkmc_mumu.txt'
else:
b2.B2FATAL("add_kkmc_generator final state not supported: {}".format(finalstate))
# use KKMC to generate lepton pairs
path.add_module(
'KKGenInput',
tauinputFile=kkmc_inputfile,
KKdefaultFile=kkmc_config,
taudecaytableFile=kkmc_tauconfigfile,
kkmcoutputfilename=kkmc_logfile,
eventType=eventType,
)
[docs]def add_evtgen_generator(path, finalstate='', signaldecfile=None, coherentMixing=True, parentParticle='Upsilon(4S)', eventType=''):
"""
Add EvtGen for mixed and charged BB
Parameters:
path (basf2.Path): path where the generator should be added
finalstate (str): Either "charged" for generation of generic B+/B-, "mixed" for generic B0/anti-B0, or "signal" for
generation of user-defined signal mode
signaldecfile (str): path to decfile which defines the signal decay to be generated
(only needed if ``finalstate`` set to "signal")
coherentMixing: Either True or False. Switches on or off the coherent decay of the B0-B0bar pair.
It should always be True, unless you are generating Y(5,6S) -> BBar. In the latter case,
setting it False solves the internal limitation of Evtgen that allows to make a
coherent decay only starting from the Y(4S).
parentParticle (str): initial state (used only if it is not Upsilon(4S).
eventType (str) : event type information
"""
evtgen_userdecfile = b2.find_file('data/generators/evtgen/charged.dec')
if parentParticle != 'Upsilon(3S)' and parentParticle != 'Upsilon(4S)'\
and parentParticle != 'Upsilon(5S)' and parentParticle != 'Upsilon(6S)':
b2.B2FATAL("add_evtgen_generator initial state not supported: {}".format(parentParticle))
if finalstate == 'charged':
pass
elif finalstate == 'mixed':
evtgen_userdecfile = b2.find_file('data/generators/evtgen/mixed.dec')
elif finalstate == 'signal':
evtgen_userdecfile = signaldecfile
else:
b2.B2FATAL("add_evtgen_generator final state not supported: {}".format(finalstate))
if signaldecfile and finalstate in ['charged', 'mixed']:
b2.B2WARNING("ignoring decfile: {}".format(signaldecfile))
# use EvtGen
if parentParticle == 'Upsilon(3S)':
if finalstate != 'signal':
b2.B2FATAL("add_evtgen_generator initial state {} is supported only with 'signal' final state".format(parentParticle))
if coherentMixing:
coherentMixing = False
b2.B2WARNING("add_evtgen_generator initial state {} has no BB mixing, now switching coherentMixing OFF"
.format(parentParticle))
if parentParticle == 'Upsilon(5S)':
if finalstate != 'signal':
b2.B2FATAL("add_evtgen_generator initial state {} is supported only with 'signal' final state".format(parentParticle))
if coherentMixing:
coherentMixing = False
b2.B2WARNING(
"add_evtgen_generator initial state {} is supported only with false coherentMixing, now switching it OFF"
.format(parentParticle))
pdg.load(b2.find_file('decfiles/dec/Y5S.pdl'))
if parentParticle == 'Upsilon(6S)':
if finalstate != 'signal':
b2.B2FATAL("add_evtgen_generator initial state {} is supported only with 'signal' final state".format(parentParticle))
if coherentMixing:
coherentMixing = False
b2.B2WARNING(
"add_evtgen_generator initial state {} is supported only with false coherentMixing, now switching it OFF"
.format(parentParticle))
pdg.load(b2.find_file('decfiles/dec/Y6S.pdl'))
path.add_module(
'EvtGenInput',
userDECFile=evtgen_userdecfile,
CoherentMixing=coherentMixing,
ParentParticle=parentParticle,
eventType=eventType,
)
[docs]def add_continuum_generator(path, finalstate, userdecfile='', *, skip_on_failure=True, eventType=''):
"""
Add the default continuum generators KKMC + PYTHIA including their default decfiles and PYTHIA settings
See Also:
`add_inclusive_continuum_generator()` to add continuum generation with preselected particles
Parameters:
path (basf2.Path): path where the generator should be added
finalstate (str): uubar, ddbar, ssbar, ccbar
userdecfile (str): EvtGen decfile used for particle decays
skip_on_failure (bool): If True stop event processing right after
fragmentation fails. Otherwise continue normally
eventType (str) : event type information
"""
#: kkmc input file, one for each qqbar mode
kkmc_inputfile = b2.find_file('data/generators/kkmc/uubar_nohadronization.input.dat')
#: kkmc file that will hold cross section and other information
kkmc_logfile = 'kkmc_uubar.txt'
#: pythia configuration, different for ccbar
pythia_config = b2.find_file('data/generators/modules/fragmentation/pythia_belle2.dat')
#: user decay file
decay_user = b2.find_file('data/generators/modules/fragmentation/dec_belle2_qqbar.dec')
if userdecfile == '':
pass
else:
b2.B2INFO('Replacing default user decfile: {}'.format(userdecfile))
decay_user = userdecfile
#: kkmc configuration file, should be fine as is
kkmc_config = b2.find_file('data/generators/kkmc/KK2f_defaults.dat')
#: global decay file
decay_file = get_default_decayfile()
if finalstate == 'uubar':
pass
elif finalstate == 'ddbar':
kkmc_inputfile = b2.find_file('data/generators/kkmc/ddbar_nohadronization.input.dat')
kkmc_logfile = 'kkmc_ddbar.txt'
elif finalstate == 'ssbar':
kkmc_inputfile = b2.find_file('data/generators/kkmc/ssbar_nohadronization.input.dat')
kkmc_logfile = 'kkmc_ssbar.txt'
elif finalstate == 'ccbar':
kkmc_inputfile = b2.find_file('data/generators/kkmc/ccbar_nohadronization.input.dat')
pythia_config = b2.find_file('data/generators/modules/fragmentation/pythia_belle2_charm.dat')
kkmc_logfile = 'kkmc_ccbar.txt'
else:
b2.B2FATAL("add_continuum_generator final state not supported: {}".format(finalstate))
# use KKMC to generate qqbar events (no fragmentation at this stage)
path.add_module(
'KKGenInput',
tauinputFile=kkmc_inputfile,
KKdefaultFile=kkmc_config,
taudecaytableFile='',
kkmcoutputfilename=kkmc_logfile,
eventType=eventType,
)
# add the fragmentation module to fragment the generated quarks into hadrons
# using PYTHIA8
fragmentation = path.add_module(
'Fragmentation',
ParameterFile=pythia_config,
ListPYTHIAEvent=0,
UseEvtGen=1,
DecFile=decay_file,
UserDecFile=decay_user,
)
if skip_on_failure:
# branch to an empty path if PYTHIA failed, this will change the number of events
# but the file meta data will contain the total number of generated events
generator_emptypath = b2.create_path()
fragmentation.if_value('<1', generator_emptypath)
[docs]def add_inclusive_continuum_generator(path, finalstate, particles, userdecfile='',
*, include_conjugates=True, max_iterations=100000, eventType=''):
"""
Add continuum generation but require at least one of the given particles be
present in the event.
For example to only generate ccbar events which contain a "D*+" or an
electron one could would use
>>> add_inclusive_continuum_generator(path, "ccbar", ["D*+", 11])
If you are unsure how the particles are named in Belle II please have a look
at the ``b2help-particles`` executable or the `pdg` python module.
See Also:
`add_continuum_generator()` to add continuum generation without preselection
Parameters:
path (basf2.Path): path to which the generator should be added
finalstate (str): uubar, ddbar, ssbar, ccbar
particles (list): A list of particle names or pdg codes. An event is
only accepted if at lease one of those particles appears in the event.
userdecfile (str): EvtGen decfile used for particle decays
include_conjugates (bool): If True (default) accept the event also if a
charge conjugate of the given particles is found
max_iterations (int): maximum tries per event to generate the requested
particle. If exceeded processing will be stopped with a
`FATAL <LogLevel.FATAL>` error so for rare particles one might need a
larger number.
eventType (str) : event type information
"""
loop_path = b2.create_path()
# we might run this more than once so make sure we remove any particles
# before generating new ones
loop_path.add_module("PruneDataStore", keepMatchedEntries=False, matchEntries=["MCParticles", "EventExtraInfo"])
# add the generator but make sure it doesn't stop processing on
# fragmentation failure as is this currently not supported by do_while
add_continuum_generator(loop_path, finalstate, userdecfile, skip_on_failure=False, eventType=eventType)
# check for the particles we want
loop_path.add_module("InclusiveParticleChecker", particles=particles, includeConjugates=include_conjugates)
# Done, add this to the path and iterate it until we found our particle
path.do_while(loop_path, max_iterations=max_iterations)
[docs]def add_bhwide_generator(path, minangle=0.5):
"""
Add the high precision QED generator BHWIDE to the path. Settings are the default L1/HLT study settings
with a cross section of about 124000 nb (!)
Parameters:
path (basf2.Path): path where the generator should be added
minangle (float): minimum angle of the outgoing electron/positron in the CMS in degrees
"""
if minangle < 0.0 or minangle > 180.0:
b2.B2FATAL("add_bhwide_generator minimum angle too small (<0.0) or too large (>180): {}".format(minangle))
bhwide = path.add_module("BHWideInput")
bhwide.param('ScatteringAngleRangePositron', [minangle, 180.0 - minangle])
bhwide.param('ScatteringAngleRangeElectron', [minangle, 180.0 - minangle])
bhwide.param('MaxAcollinearity', 180.0)
bhwide.param('MinEnergy', 0.10)
bhwide.param('VacuumPolarization', 'burkhardt')
bhwide.param('WeakCorrections', True)
bhwide.param('WtMax', 3.0)
[docs]def add_babayaganlo_generator(
path,
finalstate='',
minenergy=0.01,
minangle=10.0,
fmax=-1.0,
generateInECLAcceptance=False,
eventType=''):
'''
Add the high precision QED generator BabaYaga@NLO to the path.
Parameters:
path (basf2.Path): path where the generator should be added.
finalstate (str): ee (e+e-) or gg (gammagamma).
minenergy (float): minimum particle (leptons for 'ee', photons for 'gg') energy in GeV.
minangle (float): angular range from minangle to 180-minangle for primary particles (in degrees).
fmax (float): maximum of differential cross section weight. This parameter should be set only by experts.
generateInECLAcceptance (bool): if True, the GeneratorPreselection module is used to select only events
with both the primary particles within the ECL acceptance.
eventType (str) : event type information
'''
babayaganlo = path.add_module('BabayagaNLOInput')
babayaganlo.param('eventType', eventType)
if not (fmax == -1.0):
b2.B2WARNING(f'The BabayagaNLOInput parameter "FMax" will be set to {fmax} instead to the default value (-1.0). '
'Please do not do this, unless you are extremely sure about this choice.')
if finalstate == 'ee':
babayaganlo.param('FinalState', 'ee')
babayaganlo.param('ScatteringAngleRange', [minangle, 180.0 - minangle])
babayaganlo.param('MinEnergy', minenergy)
babayaganlo.param('FMax', fmax)
elif finalstate == 'gg':
babayaganlo.param('FinalState', 'gg')
babayaganlo.param('ScatteringAngleRange', [minangle, 180.0 - minangle])
babayaganlo.param('MinEnergy', minenergy)
babayaganlo.param('FMax', fmax)
else:
b2.B2FATAL(f'add_babayaganlo_generator final state not supported: {finalstate}')
if generateInECLAcceptance:
b2.B2INFO(f'The final state {finalstate} is preselected requiring both primary particles within the ECL acceptance.')
emptypath = b2.Path()
add_generator_preselection(path=path,
emptypath=emptypath,
applyInCMS=False)
if finalstate == 'ee':
b2.set_module_parameters(path=path,
name='GeneratorPreselection',
nChargedMin=2,
MinChargedTheta=12.4,
MaxChargedTheta=155.1,)
elif finalstate == 'gg':
b2.set_module_parameters(path=path,
name='GeneratorPreselection',
nPhotonMin=2,
MinPhotonTheta=12.4,
MaxPhotonTheta=155.1)
[docs]def add_phokhara_generator(path, finalstate='', eventType=''):
"""
Add the high precision QED generator PHOKHARA to the path. Almost full
acceptance settings for photons and hadrons/muons.
Parameters:
path (basf2.Path): path where the generator should be added
finalstate (str): One of the following final states: "mu+mu-", "pi+pi-", "pi+pi-pi0", "pi+pi-pi+pi-" (or "2(pi+pi-)"),
"pi+pi-pi0pi0" or ("pi+pi-2pi0"), "pi+pi-eta", "K+K-", "K0K0bar", "ppbar", "n0n0bar" or "Lambda0Lambda0bar"
eventType (str) : event type information
"""
if finalstate == 'mu+mu-':
path.add_module(
'PhokharaInput',
FinalState=0, # mu+mu-
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_mumuISR')
elif finalstate == 'pi+pi-':
path.add_module(
'PhokharaInput',
FinalState=1, # pi+pi-
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_pipiISR')
elif finalstate == 'pi+pi-pi0':
path.add_module(
'PhokharaInput',
FinalState=8, # pi+pi-pi0
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_pipipi0ISR')
elif finalstate == 'pi+pi-pi+pi-' or finalstate == '2(pi+pi-)':
path.add_module(
'PhokharaInput',
FinalState=3, # 2(pi+pi-)
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_pipipipiISR')
elif finalstate == 'pi+pi-pi0pi0' or finalstate == 'pi+pi-2pi0':
path.add_module(
'PhokharaInput',
FinalState=2, # pi+pi-2pi0
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_pipipi0pi0ISR')
elif finalstate == 'pi+pi-eta':
path.add_module(
'PhokharaInput',
FinalState=10, # pi+pi-eta
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_pipietaISR')
elif finalstate == 'K+K-':
path.add_module(
'PhokharaInput',
FinalState=6, # K+K-
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_KKISR')
elif finalstate == 'K0K0bar':
path.add_module(
'PhokharaInput',
FinalState=7, # K0K0bar
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_K0K0barISR')
elif finalstate == 'ppbar':
path.add_module(
'PhokharaInput',
FinalState=4, # ppbar
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_ppbarISR')
elif finalstate == 'n0n0bar':
path.add_module(
'PhokharaInput',
FinalState=5, # n0n0bar
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_n0n0barISR')
elif finalstate == 'Lambda0Lambda0bar':
path.add_module(
'PhokharaInput',
FinalState=9, # Lambda0Lambda0bar
LO=0, NLO=1, QED=0, # use full two loop corrections
MinInvMassHadrons=0.,
eventType=eventType,
).set_name('PHOKHARA_Lambda0Lambda0barISR')
else:
b2.B2FATAL(f"add_phokhara_generator final state not supported: {finalstate}")
[docs]def add_phokhara_evtgen_combination(
path, final_state_particles, user_decay_file,
beam_energy_spread=True, isr_events=False, min_inv_mass_vpho=0.0,
max_inv_mass_vpho=0.0, eventType=''):
"""
Add combination of PHOKHARA and EvtGen to the path. Phokhara is
acting as ISR generator by generating e+ e- -> mu+ mu-, the muon pair is
then replaced by a virtual photon. Finally, the virtual photon is
decayed by EvtGen.
Parameters:
path (basf2.Path): Path where the generator should be added.
final_state_particles (list): List of final-state particles of
the virtual-photon decay. It is necessary to define the correct
mass threshold in PHOKHARA. For example, for the process
e+ e- -> J/psi eta_c, the list should be ['J/psi', 'eta_c'];
it does not depend on subsequent J/psi or eta_c decays.
user_decay_file (str): Name of EvtGen user decay file. The initial
particle must be the virtual photon (vpho).
beam_energy_spread (bool): Whether beam-energy spread should be
simulated
isr_events (bool): If true, then PHOKHARA is used with ph0 (LO in
basf2) = 0, i.e. generation of processes with one photon.
min_inv_mass_hadrons(float): Minimum invariant mass of the virtual
photon. This parameter is used only if isr_events is true,
otherwise the minimum mass is computed from the masses of
the final-state particles.
max_inv_mass_hadrons(float): Maximum invariant mass of the virtual
photon. This parameter is used only if isr_events is true,
otherwise the maximum mass is not restricted.
eventType (str) : event type information
"""
import pdg
phokhara = path.add_module('PhokharaInput')
phokhara.param('eventType', eventType)
# Generate muons and replace them by a virtual photon.
phokhara.param('FinalState', 0)
phokhara.param('ReplaceMuonsByVirtualPhoton', True)
# Simulate beam-energy spread. This performs initialization for every
# event, and, thus, very slow, but usually necessary except for testing.
phokhara.param('BeamEnergySpread', beam_energy_spread)
# Soft photon cutoff.
phokhara.param('Epsilon', 0.0001)
# Maximum search.
phokhara.param('SearchMax', 5000)
# Number of generation attempts for event.
phokhara.param('nMaxTrials', 25000)
# Use NNLO.
if isr_events:
phokhara.param('LO', 0)
else:
phokhara.param('LO', 1)
phokhara.param('NLO', 1)
# Use ISR only.
phokhara.param('QED', 0)
# No interference.
phokhara.param('IFSNLO', 0)
# Vacuum polarization by Fred Jegerlehner.
phokhara.param('Alpha', 1)
# Do not include narrow resonances.
phokhara.param('NarrowRes', 0)
# Angular ragnes.
phokhara.param('ScatteringAngleRangePhoton', [0., 180.])
phokhara.param('ScatteringAngleRangeFinalStates', [0., 180.])
# Minimal invariant mass of the muons and tagged photon combination.
phokhara.param('MinInvMassHadronsGamma', 0.)
if isr_events:
# Minimum squared invariant mass of muons (final state).
phokhara.param('MinInvMassHadrons',
min_inv_mass_vpho * min_inv_mass_vpho)
# Maximum squared invariant mass of muons (final state).
phokhara.param('MaxInvMassHadrons',
max_inv_mass_vpho * max_inv_mass_vpho)
else:
# Minimum squared invariant mass of muons (final state).
# Force application of this cut.
mass = 0
for particle in final_state_particles:
p = pdg.get(particle)
mass = mass + p.Mass()
phokhara.param('MinInvMassHadrons', mass * mass)
phokhara.param('ForceMinInvMassHadronsCut', True)
# Maximum squared invariant mass of muons (final state).
# It is set to a large value, resulting in unrestricted mass.
phokhara.param('MaxInvMassHadrons', 200.0)
# Minimal photon energy.
phokhara.param('MinEnergyGamma', 0.01)
# EvtGen.
evtgen_decay = path.add_module('EvtGenDecay')
evtgen_decay.param('UserDecFile', user_decay_file)
[docs]def add_koralw_generator(path, finalstate='', enableTauDecays=True, eventType=''):
"""
Add KoralW generator for radiative four fermion final states (only four leptons final states are currently supported).
Parameters:
path (basf2.Path): path where the generator should be added
finalstate (str): either 'e+e-e+e-', 'e+e-mu+mu-', 'e+e-tau+tau-', 'mu+mu-mu+mu-', 'mu+mu-tau+tau-' or 'tau+tau-tau+tau-'
enableTauDecays (bool): if True, allow tau leptons to decay (using EvtGen)
eventType (str) : event type information
"""
decayFile = ''
if finalstate == 'e+e-e+e-':
decayFile = b2.find_file('data/generators/koralw/KoralW_eeee.data')
elif finalstate == 'e+e-mu+mu-':
decayFile = b2.find_file('data/generators/koralw/KoralW_eeMuMu.data')
elif finalstate == 'e+e-tau+tau-':
decayFile = b2.find_file('data/generators/koralw/KoralW_eeTauTau.data')
elif finalstate == 'mu+mu-mu+mu-':
decayFile = b2.find_file('data/generators/koralw/KoralW_MuMuMuMu.data')
elif finalstate == 'mu+mu-tau+tau-':
decayFile = b2.find_file('data/generators/koralw/KoralW_MuMuTauTau.data')
elif finalstate == 'tau+tau-tau+tau-':
decayFile = b2.find_file('data/generators/koralw/KoralW_TauTauTauTau.data')
else:
b2.B2FATAL(f'add_koralw_generator final state not supported: {finalstate}')
path.add_module('KoralWInput',
UserDataFile=decayFile,
eventType=eventType)
if 'tau+tau-' in finalstate:
if enableTauDecays:
path.add_module('EvtGenDecay')
else:
b2.B2WARNING('The tau decays will not be generated.')
[docs]def add_cosmics_generator(path, components=None,
global_box_size=None, accept_box=None, keep_box=None,
geometry_xml_file='geometry/Beast2_phase2.xml',
cosmics_data_dir='data/generators/modules/cryinput/',
setup_file='generators/scripts/cry.setup',
data_taking_period='gcr2017', top_in_counter=False):
"""
Add the cosmics generator CRY with the default parameters to the path.
Warning:
Please remember to also change the reconstruction accordingly, if you
set "special" parameters here!
Parameters:
path (basf2.Path): path where the generator should be added
components (list(str)): list of geometry components to add in the
geometry module, or None for all components.
global_box_size (tuple(float, float, float)): sets global length, width
and height (in meters) in which to generate.
Default is ``[100, 100, 100]``
accept_box (tuple(float, float, float)): sets the size of the accept box in meter.
As a default it is set to ``[8.0, 8.0, 8.0]`` (the Belle II detector size).
keep_box (tuple(float, float, float)): sets the size of the keep box (keep box >= accept box).
geometry_xml_file (str): Name of the xml file to use for the geometry.
cosmics_data_dir (str): parameter CosmicDataDir for the cry module (absolute or relative to the basf2 repo).
setup_file (str): location of the cry.setup file (absolute or relative to the basf2 repo)
data_taking_period (str): The cosmics generation will be added using the
parameters, that where used in this period of data taking. The
periods can be found in ``cdc/cr/__init__.py``.
top_in_counter (bool): time of propagation from the hit point to the PMT in the trigger counter is subtracted
(assuming PMT is put at -z of the counter).
"""
b2.B2FATAL('''The function "add_cosmics_generator()" is outdated and it is currently not working: please replace
add_cosmics_generator(path=path)
with
path.add_module('CRYInput')
in your steering file (the module parameter "acceptance" has to be set, see the module docummentation).''')
import cdc.cr as cosmics_setup
if global_box_size is None:
global_box_size = [100, 100, 100]
if accept_box is None:
accept_box = [8, 8, 8]
if keep_box is None:
keep_box = [8, 8, 8]
cosmics_setup.set_cdc_cr_parameters(data_taking_period)
if cosmics_setup.cosmics_period == "201607":
b2.B2FATAL("The data taking period 201607 is very special (geometry setup, PMTs etc). This is not handled "
"by this script! Please ask the CDC group, if you want to simulate this.")
if 'Gearbox' not in path:
override = [("/Global/length", str(global_box_size[0]), "m"),
("/Global/width", str(global_box_size[1]), "m"),
("/Global/height", str(global_box_size[2]), "m")]
if cosmics_setup.globalPhi:
override += [("/DetectorComponent[@name='CDC']//GlobalPhiRotation", str(cosmics_setup.globalPhi), "deg")]
path.add_module('Gearbox', override=override, fileName=geometry_xml_file,)
# detector geometry
if 'Geometry' not in path:
geometry = path.add_module('Geometry')
if components:
geometry.param('components', components)
cry = path.add_module('CRYInput')
# cosmic data input
cry.param('CosmicDataDir', b2.find_file(cosmics_data_dir))
# user input file
cry.param('SetupFile', b2.find_file(setup_file))
# acceptance half-lengths - at least one particle has to enter that box to use that event
cry.param('acceptLength', accept_box[0])
cry.param('acceptWidth', accept_box[1])
cry.param('acceptHeight', accept_box[2])
cry.param('maxTrials', 100000)
# keep half-lengths - all particles that do not enter the box are removed (keep box >= accept box)
# default was 6.0
cry.param('keepLength', keep_box[0])
cry.param('keepWidth', keep_box[1])
cry.param('keepHeight', keep_box[2])
# minimal kinetic energy - all particles below that energy are ignored
cry.param('kineticEnergyThreshold', 0.01)
# TODO: I still do not fully understand, when the cosmics selector is needed and when not
if cosmics_setup.cosmics_period not in ["normal", "gcr2017"]:
# Selector module.
cosmics_selector = b2.register_module('CDCCosmicSelector',
lOfCounter=cosmics_setup.lengthOfCounter,
wOfCounter=cosmics_setup.widthOfCounter,
xOfCounter=cosmics_setup.triggerPos[0],
yOfCounter=cosmics_setup.triggerPos[1],
zOfCounter=cosmics_setup.triggerPos[2],
phiOfCounter=0.,
TOP=top_in_counter,
propSpeed=cosmics_setup.lightPropSpeed,
TOF=1,
cryGenerator=True
)
path.add_module(cosmics_selector)
empty_path = b2.create_path()
cosmics_selector.if_false(empty_path)
[docs]def add_treps_generator(path, finalstate='', useDiscreteAndSortedW=False, eventType=''):
"""
Add TREPS generator to produce hadronic two-photon processes.
Parameters:
path (basf2.Path): path where the generator should be added
finalstate(str): "e+e-pi+pi-", "e+e-K+K-" or "e+e-ppbar"
useDiscreteAndSortedW(bool): if True, wListTableFile is used for discrete and sorted W. evtNumList must be set proper value.
eventType (str) : event type information
"""
if finalstate == 'e+e-pi+pi-':
parameterFile = b2.find_file('generators/treps/data/parameterFiles/treps_par_pipi.dat')
differentialCrossSectionFile = b2.find_file('generators/treps/data/differentialCrossSectionFiles/pipidcs.dat')
wListTableFile = b2.find_file('generators/treps/data/wListFiles/wlist_table_pipi.dat')
elif finalstate == 'e+e-K+K-':
parameterFile = b2.find_file('generators/treps/data/parameterFiles/treps_par_kk.dat')
differentialCrossSectionFile = b2.find_file('generators/treps/data/differentialCrossSectionFiles/kkdcs.dat')
wListTableFile = b2.find_file('generators/treps/data/wListFiles/wlist_table_kk.dat')
elif finalstate == 'e+e-ppbar':
parameterFile = b2.find_file('generators/treps/data/parameterFiles/treps_par_ppbar.dat')
differentialCrossSectionFile = b2.find_file('generators/treps/data/differentialCrossSectionFiles/ppbardcs.dat')
wListTableFile = b2.find_file('generators/treps/data/wListFiles/wlist_table_ppbar.dat')
else:
b2.B2FATAL("add_treps_generator final state not supported: {}".format(finalstate))
# use TREPS to generate two-photon events.
path.add_module(
'TrepsInput',
ParameterFile=parameterFile,
DifferentialCrossSectionFile=differentialCrossSectionFile,
WListTableFile=wListTableFile,
UseDiscreteAndSortedW=useDiscreteAndSortedW,
MaximalQ2=1.0,
MaximalAbsCosTheta=1.01,
ApplyCosThetaCutCharged=True,
MinimalTransverseMomentum=0,
ApplyTransverseMomentumCutCharged=True,
eventType=eventType,
)
