def update_dipoles_g_split_RHS_recoil(self,pC,cC,nV1,nV2,nV3): """A function to update the relevant dipoles when a gluon is split with the RHS recoiling.""" assert ((counters.check_is_counter(pC)) and (counters.check_is_counter(cC))) for nV in [nV1,nV2,nV3]: assert fourVectors.check_is_fourVector(nV) assert (self.__maxPperpSquared > self.__cutOff) __p1B = self.__chainList[self.__nextIndex][0].copy() __p1BMs, __p1BCs = [__p1B.get_mother(0),__p1B.get_mother(1)], [__p1B.get_child(0),__p1B.get_child(1)] __qCode = quarkPairs.get_quark_code(self.__maxPperpSquared,self.__activeQCodes) ##As maxPperpSquared now set to S123 of splitting. producedQuarkCodes.store(__qCode) __p1C0B, __p1C1B = __p1B.get_colour(0), __p1B.get_colour(1) __p1 = particles.particle(-__qCode,__p1B.get_four_momentum(),__p1BMs,__p1BCs,[0,0],__p1B.get_status_code()) __p2 = particles.particle(__qCode,nV2,[0,0],[0,0],[0,0],1) __p3 = self.__chainList[self.__nextIndex][1].copy() __p1.set_four_momentum(nV1) __p3.set_four_momentum(nV3) __p1.set_unique_ID(pC.next()) ##Set unique particle IDs when produced. __p2.set_unique_ID(pC.next()) __p1.set_produced_at(self.__maxPperpSquared) ##As now set to that of this produced particle. __p2.set_produced_at(self.__maxPperpSquared) __p1.set_mother(0,__p3.get_unique_ID()) __p2.set_mother(1,__p3.get_unique_ID()) if __p3.get_child(0) != 0: ##i.e don't overwrite. __p3.set_child(0,__p2.get_unique_ID()) __p1, __p2, __p3 = self.set_new_colours_g_split(cC,__p1,__p2,__p3, __p1C0B, __p1C1B,"RHS") __nDPLHS = self.__chainList[self.__nextIndex].copy() __nDPRHS = self.__chainList[self.__nextIndex].copy() __nDPLHS[0], __nDPLHS[1] = __p1.copy(), __p2.copy() __nDPRHS[0], __nDPRHS[1] = __p2.copy(), __p3.copy() self.update_dipole_values(__p1.copy(),__nDPLHS,__nDPRHS,__p3.copy()) self.__sideOfSplit = "RHS"
def evolve(self,activeQCodes,pC,cC): """A function to evolve a chain through the next event if one is possible.""" assert ((counters.check_is_counter(pC)) and (counters.check_is_counter(cC))) for __dipole in self.__chainList: assert __dipole.is_updated() assert (type(activeQCodes) == list) for qCode in activeQCodes: assert qCode in particleData.knownParticles.get_known_quarks() self.__activeQCodes = activeQCodes ##If self.__maxPperpSquared > self.__cutOff, should get not self.__proceed. self.run_sudakovs() ##Get values and process for each dipole. self.__proceed = self.process_sudakovs() ##Work out what's happening next. if (not self.__proceed): self.set_showering_completed() return [0,None] else: self.prepare_dipoles() __nV1, __nV2, __nV3 = self.run_kinematics() if (self.__nextProcessCode == 1): ##Gluon emission. self.update_dipoles_g_prod(pC,cC,__nV1, __nV2, __nV3) return [1,None] elif (self.__nextProcessCode == 2): ##Gluon splitting. #Currently doesn't account for loops self.update_dipoles_g_split(pC,cC,__nV1, __nV2, __nV3) if (self.__sideOfSplit == "LHS"): ##i.e RHS is gluon splitting. __splitBeforeIndex = self.__nextIndex + 1 elif (self.__sideOfSplit == "RHS"): ##i.e LHS is gluon splitting. __splitBeforeIndex = self.__nextIndex return [2,[__splitBeforeIndex,self.__nextPperpSquared]] elif (self.__nextProcessCode == 3): ##Photon emission. self.update_dipoles_p_prod(pC,__nV1,__nV2,__nV3) return [3,self.__producedPhoton]
def update_dipoles_g_prod_RHS_recoil(self,pC,cC,nV1,nV2,nV3):
"""A function to update the relevant dipoles when a gluon is produced with the RHS recoiling."""
assert ((counters.check_is_counter(pC)) and (counters.check_is_counter(cC)))
for nV in [nV1,nV2,nV3]:
assert fourVectors.check_is_fourVector(nV)
assert (self.__maxPperpSquared > self.__cutOff)
__p1 = self.__chainList[self.__nextIndex][0].copy()
__p2 = particles.particle('gluon',nV2,[0,0],[0,0],[0,0],1)
__p3 = self.__chainList[self.__nextIndex][1].copy()
__p1.set_four_momentum(nV1)
__p3.set_four_momentum(nV3)
__p2.set_unique_ID(pC.next()) ##Set unique particle ID when produced.
__p2.set_produced_at(self.__maxPperpSquared) ##As now set to that of this produced particle.
__p2.set_mother(0,__p1.get_unique_ID())
__p2.set_mother(1,__p3.get_unique_ID())
if __p1.get_child(1) != 0: ##i.e don't overwrite
__p1.set_child(1,__p2.get_unique_ID())
if __p3.get_child(0) != 0: ##i.e don't overwrite
__p3.set_child(0,__p2.get_unique_ID())
__p1, __p2, __p3 = self.set_new_colours_g_prod(cC,__p1,__p2,__p3)
__nDPLHS = self.__chainList[self.__nextIndex].copy()
__nDPRHS = self.__chainList[self.__nextIndex].copy()
__nDPLHS[0], __nDPLHS[1] = __p1.copy(), __p2.copy()
__nDPRHS[0], __nDPRHS[1] = __p2.copy(), __p3.copy()
self.update_dipole_values(__p1.copy(),__nDPLHS,__nDPRHS,__p3.copy())
def update_dipoles_g_split(self,pC,cC,nV1,nV2,nV3): """A function to update the relevant dipoles when a gluon is split.""" assert ((counters.check_is_counter(pC)) and (counters.check_is_counter(cC))) for nV in [nV1,nV2,nV3]: assert fourVectors.check_is_fourVector(nV) assert (self.__maxPperpSquared > self.__cutOff) if (self.__dipoleRecoilIndex == 0): ##LHS recoiling. self.update_dipoles_g_split_LHS_recoil(pC,cC,nV1,nV2,nV3) else: ##RHS recoiling. self.update_dipoles_g_split_RHS_recoil(pC,cC,nV1,nV2,nV3)
def set_new_colours_g_split(self,cC,p1,p2,p3,p1C0B,p1C1B,hS):
"""A function to set the new colours of the produced particles."""
assert counters.check_is_counter(cC)
for p in [p1,p2,p3]:
assert particles.check_is_particle(p)
assert p.__nonzero__()
assert ((type(p1C0B) == int) and (type(p1C1B) == int))
assert ((hS == "LHS") or (hS == "RHS"))
__kQs = particleData.knownParticles.get_known_quarks()
__gC = particleData.knownParticles.get_code_from_name('gluon')
if (hS == "LHS"):
if (p1.get_code() > 0): ##Q
p1.set_colour(0,p1C0B)
p2.set_colour(1,p1C1B)
else: ##QBar
p1.set_colour(0,p1C0B)
p2.set_colour(1,p1C1B)
elif (hS == "RHS"):
if (p1.get_code() > 0): ##Q
p1.set_colour(1,p1C0B)
p2.set_colour(0,p1C1B)
else: ##QBar
p1.set_colour(1,p1C1B)
p2.set_colour(0,p1C0B)
return p1, p2, p3
def update_dipoles_p_prod(self,pC,nV1,nV2,nV3): """A function to update the relevant dipoles when a photon is emitted.""" assert counters.check_is_counter(pC) for nV in [nV1,nV2,nV3]: assert fourVectors.check_is_fourVector(nV) assert (self.__maxPperpSquared > self.__cutOff) if (self.__dipoleRecoilIndex == 0): ##LHS recoiling. self.update_dipoles_p_prod_LHS_recoil(pC,nV1,nV2,nV3) else: ##RHS recoiling. self.update_dipoles_p_prod_RHS_recoil(pC,nV1,nV2,nV3)
def set_new_colours_g_prod(self,cC,p1,p2,p3):
"""A function to set the new colours of the produced particles."""
assert counters.check_is_counter(cC)
for p in [p1,p2,p3]:
assert particles.check_is_particle(p)
assert p.__nonzero__()
__kQs = particleData.knownParticles.get_known_quarks()
__gC = particleData.knownParticles.get_code_from_name('gluon')
if ((p1.get_code() in __kQs) and ((-p3.get_code()) in __kQs)): ##qqBar.
__nC = cC.next()
p2.set_colour(0,__nC)
p2.set_colour(1,p1.get_colour(0))
p3.set_colour(1,__nC)
elif (((-p1.get_code()) in __kQs) and (p3.get_code() in __kQs)): ##qBarq.
__nC = cC.next()
p1.set_colour(1,__nC)
p2.set_colour(0,__nC)
p2.set_colour(1,p3.get_colour(0))
elif ((p1.get_code() in __kQs) and (p3.get_code() == __gC)): ##qg.
__nC = cC.next()
p2.set_colour(0,__nC)
p2.set_colour(1,p1.get_colour(0))
p3.set_colour(1,__nC)
elif (((-p1.get_code()) in __kQs) and (p3.get_code() == __gC)): ##qBarg.
__nC = cC.next()
p2.set_colour(0,p1.get_colour(1))
p2.set_colour(1,__nC)
p3.set_colour(0,__nC)
elif ((p1.get_code() == __gC) and (p3.get_code() in __kQs)): ##gq.
__nC = cC.next()
p1.set_colour(1,__nC)
p2.set_colour(0,__nC)
p2.set_colour(1,p3.get_colour(0))
elif ((p1.get_code() == __gC) and ((-p3.get_code()) in __kQs)): ##gqBar.
__nC = cC.next()
p1.set_colour(0,__nC)
p2.set_colour(0,p3.get_colour(1))
p2.set_colour(1,__nC)
elif ((p1.get_code() == __gC) and (p3.get_code() == __gC)): ##gg.
##Two possibilities so randomly choose which keeps colour code.
__R = random.random()
if (self.__dipoleRecoilIndex == 0): ##qBar at p3 end, i.e LHS.
if (__R < 0.5): ##Choose option A.
__nC = cC.next()
p1.set_colour(1,__nC)
p2.set_colour(0,__nC)
p2.set_colour(1,p3.get_colour(0))
else: ##Choose option B.
__nC = cC.next()
p2.set_colour(0,p1.get_colour(1))
p2.set_colour(1,__nC)
p3.set_colour(0,__nC)
else: ##q at p3 end, i.e RHS.
if (__R < 0.5): ##Choose option A.
__nC = cC.next()
p2.set_colour(0,__nC)
p2.set_colour(1,p1.get_colour(0))
p3.set_colour(1,__nC)
else: ##Choose option B.
__nC = cC.next()
p1.set_colour(0,__nC)
p2.set_colour(0,p3.get_colour(1))
p2.set_colour(1,__nC)
return p1, p2, p3