From 91cd9ffac2e34c9e802f8e1d80f5c843aa96af81 Mon Sep 17 00:00:00 2001 From: Ye Chen Date: Wed, 19 Feb 2014 17:30:11 +0100 Subject: [PATCH 1/2] Create LambdaB_Psi2SLambda_ppi.dec Add BPH decay file --- .../data/LambdaB_Psi2SLambda_ppi.dec | 73 +++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 GeneratorInterface/ExternalDecays/data/LambdaB_Psi2SLambda_ppi.dec diff --git a/GeneratorInterface/ExternalDecays/data/LambdaB_Psi2SLambda_ppi.dec b/GeneratorInterface/ExternalDecays/data/LambdaB_Psi2SLambda_ppi.dec new file mode 100644 index 0000000000000..e65cc5472557f --- /dev/null +++ b/GeneratorInterface/ExternalDecays/data/LambdaB_Psi2SLambda_ppi.dec @@ -0,0 +1,73 @@ +# This is the decay file for the polarized decay Lambda_B0 -> Psi(2S)(MU+ MU-) Lambda0 +# +# Descriptor: [Lambda_B0 -> Psi(2S)(mu+ mu-) Lambda0]cc +# +# NickName: +# +# Physics: Generates the correct angular distributions for polarized Lambda_b0 decay +# +# Tested: Yes +# By: B. Drell +# Date: 1-25-11 +# +# +# The helicity amplitudes are H[lambda1, lambda2] where lambda1 is the +# Lambda0 helicity and lambda2 is the J/Psi helicity: +# aPlus = H[1/2, 0] +# aMinus = H[-1/2, 0] +# bPlus = H[-1/2, -1] +# bMinus = H[1/2, 1] +# +# The correct ordering for HELAMP is highest helicity to lowest, first particle +# first. So the correct order is: +# bMinus betaMinus aPlus alphaPlus aMinus alphaMinus bPlus betaPlus +# +# These numerical values come from the ATLAS paper. +# Calculated using PQCD general amplitude coefficients. +# I need to verify that these are correct. +Define aPlus 0.423266 +Define alphaPlus -1.61239 +Define aMinus 0.257533 +Define alphaMinus 1.22743 +Define bPlus 0.295037 +Define betaPlus -1.84891 +Define bMinus 0.812939 +Define betaMinus 1.53438 +# +#Helicity amplitudes for Lambda0 decay (from Lambda0 asymmetry +#parameter alpha_Lam) +#alpha_Lam = 0.642 +- 0.013 = |hPlus|^2 - |hMinus|^2 +Define hPlus 0.906 +Define hMinus 0.423 +# +Alias MyLambda_b0 Lambda_b0 +Alias Myanti-Lambda_b0 anti-Lambda_b0 +ChargeConj MyLambda_b0 Myanti-Lambda_b0 +Alias MyLambda0 Lambda0 +Alias Myanti-Lambda0 anti-Lambda0 +ChargeConj MyLambda0 Myanti-Lambda0 +Alias MyPsi psi(2S) +ChargeConj MyPsi MyPsi +# +Decay MyLambda_b0 +1.0 MyLambda0 MyPsi HELAMP bMinus betaMinus aPlus alphaPlus aMinus alphaMinus bPlus betaPlus; +Enddecay +# +Decay Myanti-Lambda_b0 +#1.0 Myanti-Lambda0 MyJpsi HELAMP bPlus betaPlus aMinus alphaMinus aPlus alphaPlus bMinus betaMinus; +1.0 Myanti-Lambda0 MyJpsi HELAMP bMinus betaMinus aPlus alphaPlus aMinus alphaMinus bPlus betaPlus; +Enddecay +# +Decay MyLambda0 +1.0 p+ pi- HELAMP hPlus 0 hMinus 0; +Enddecay +# +Decay Myanti-Lambda0 +1.0 anti-p- pi+ HELAMP hMinus 0 hPlus 0; +Enddecay +# +Decay MyPsi +1.0 mu+ mu- PHOTOS VLL; +Enddecay +# +End From f6a400962e43a92c6c38ebe1b85af798eee04922 Mon Sep 17 00:00:00 2001 From: Ye Chen Date: Wed, 19 Feb 2014 18:00:11 +0100 Subject: [PATCH 2/2] Update LambdaB_Psi2SLambda_ppi.dec Update the BPH decay file --- .../ExternalDecays/data/LambdaB_Psi2SLambda_ppi.dec | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/GeneratorInterface/ExternalDecays/data/LambdaB_Psi2SLambda_ppi.dec b/GeneratorInterface/ExternalDecays/data/LambdaB_Psi2SLambda_ppi.dec index e65cc5472557f..c068b3302959a 100644 --- a/GeneratorInterface/ExternalDecays/data/LambdaB_Psi2SLambda_ppi.dec +++ b/GeneratorInterface/ExternalDecays/data/LambdaB_Psi2SLambda_ppi.dec @@ -54,8 +54,8 @@ Decay MyLambda_b0 Enddecay # Decay Myanti-Lambda_b0 -#1.0 Myanti-Lambda0 MyJpsi HELAMP bPlus betaPlus aMinus alphaMinus aPlus alphaPlus bMinus betaMinus; -1.0 Myanti-Lambda0 MyJpsi HELAMP bMinus betaMinus aPlus alphaPlus aMinus alphaMinus bPlus betaPlus; +#1.0 Myanti-Lambda0 MyPsi HELAMP bPlus betaPlus aMinus alphaMinus aPlus alphaPlus bMinus betaMinus; +1.0 Myanti-Lambda0 MyPsi HELAMP bMinus betaMinus aPlus alphaPlus aMinus alphaMinus bPlus betaPlus; Enddecay # Decay MyLambda0