Belle II Software  release-08-01-10
039_various_additions.py
1 #!/usr/bin/env python3
2 
3 import sys
4 import basf2 as b2
5 import modularAnalysis as ma
6 import stdV0s
7 from variables import variables as vm # shorthand for VariableManager
8 import variables.collections as vc
9 import variables.utils as vu
10 
11 # get input file number from the command line
12 filenumber = sys.argv[1]
13 
14 # create path
15 main = b2.Path()
16 
17 # load input data from mdst/udst file
18 ma.inputMdstList(
19  filelist=[b2.find_file(f"starterkit/2021/1111540100_eph3_BGx0_{filenumber}.root", "examples")],
20  path=main,
21 )
22 
23 # fill final state particle lists
24 ma.fillParticleList(
25  "e+:uncorrected",
26  "electronID > 0.1 and dr < 0.5 and abs(dz) < 2 and thetaInCDCAcceptance",
27  path=main,
28 )
29 stdV0s.stdKshorts(path=main)
30 
31 # apply Bremsstrahlung correction to electrons [S10|S20]
32 vm.addAlias(
33  "goodFWDGamma", "passesCut(clusterReg == 1 and clusterE > 0.075)"
34 ) # [E10]
35 vm.addAlias(
36  "goodBRLGamma", "passesCut(clusterReg == 2 and clusterE > 0.05)"
37 )
38 vm.addAlias(
39  "goodBWDGamma", "passesCut(clusterReg == 3 and clusterE > 0.1)"
40 )
41 vm.addAlias(
42  "goodGamma", "passesCut(goodFWDGamma or goodBRLGamma or goodBWDGamma)"
43 ) # [E20]
44 ma.fillParticleList("gamma:brems", "goodGamma", path=main)
45 ma.correctBrems("e+:corrected", "e+:uncorrected", "gamma:brems", path=main) # [S30]
46 vm.addAlias("isBremsCorrected", "extraInfo(bremsCorrected)") # [E30]
47 
48 # combine final state particles to form composite particles [S40]
49 ma.reconstructDecay(
50  "J/psi:ee -> e+:corrected e-:corrected ?addbrems",
51  cut="dM < 0.11",
52  path=main,
53 ) # [E40]
54 
55 # combine J/psi and KS candidates to form B0 candidates
56 ma.reconstructDecay(
57  "B0 -> J/psi:ee K_S0:merged",
58  cut="Mbc > 5.2 and abs(deltaE) < 0.15",
59  path=main,
60 )
61 
62 # match reconstructed with MC particles
63 ma.matchMCTruth("B0", path=main)
64 
65 # build the rest of the event
66 ma.buildRestOfEvent("B0", fillWithMostLikely=True, path=main)
67 track_based_cuts = "thetaInCDCAcceptance and pt > 0.075 and dr < 5 and abs(dz) < 10"
68 ecl_based_cuts = "thetaInCDCAcceptance and E > 0.05"
69 roe_mask = ("my_mask", track_based_cuts, ecl_based_cuts)
70 ma.appendROEMasks("B0", [roe_mask], path=main)
71 
72 # perform best candidate selection [S60]
73 b2.set_random_seed("Belle II StarterKit")
74 ma.rankByHighest("B0", variable="random", numBest=1, path=main) # [E60]
75 
76 # Create list of variables to save into the output file
77 b_vars = []
78 
79 standard_vars = vc.kinematics + vc.mc_kinematics + vc.mc_truth
80 b_vars += vc.deltae_mbc
81 b_vars += standard_vars
82 
83 # ROE variables
84 roe_kinematics = ["roeE()", "roeM()", "roeP()", "roeMbc()", "roeDeltae()"]
85 roe_multiplicities = [
86  "nROE_Charged()",
87  "nROE_Photons()",
88  "nROE_NeutralHadrons()",
89 ]
90 b_vars += roe_kinematics + roe_multiplicities
91 # Let's also add a version of the ROE variables that includes the mask:
92 for roe_variable in roe_kinematics + roe_multiplicities:
93  # e.g. instead of 'roeE()' (no mask) we want 'roeE(my_mask)'
94  roe_variable_with_mask = roe_variable.replace("()", "(my_mask)")
95  b_vars.append(roe_variable_with_mask)
96 
97 # Variables for final states (electrons, positrons, pions)
98 fs_vars = vc.pid + vc.track + vc.track_hits + standard_vars
99 b_vars += vu.create_aliases_for_selected(
100  fs_vars + ["isBremsCorrected"],
101  "B0 -> [J/psi -> ^e+ ^e-] K_S0",
102  prefix=["ep", "em"],
103 )
104 b_vars += vu.create_aliases_for_selected(
105  fs_vars, "B0 -> J/psi [K_S0 -> ^pi+ ^pi-]", prefix=["pip", "pim"]
106 )
107 # Variables for J/Psi, KS
108 jpsi_ks_vars = vc.inv_mass + standard_vars
109 b_vars += vu.create_aliases_for_selected(jpsi_ks_vars, "B0 -> ^J/psi ^K_S0")
110 # Add the J/Psi mass calculated with uncorrected electrons:
111 vm.addAlias( # [S50]
112  "Jpsi_M_uncorrected", "daughter(0, daughterCombination(M,0:0,1:0))"
113 ) # [E50]
114 b_vars += ["Jpsi_M_uncorrected"]
115 # Also add kinematic variables boosted to the center of mass frame (CMS)
116 # for all particles
117 cmskinematics = vu.create_aliases(
118  vc.kinematics, "useCMSFrame({variable})", "CMS"
119 )
120 b_vars += vu.create_aliases_for_selected(
121  cmskinematics, "^B0 -> [^J/psi -> ^e+ ^e-] [^K_S0 -> ^pi+ ^pi-]"
122 )
123 
124 vm.addAlias(
125  "withBremsCorrection",
126  "passesCut(passesCut(ep_isBremsCorrected == 1) or passesCut(em_isBremsCorrected == 1))",
127 )
128 b_vars += ["withBremsCorrection"]
129 
130 # Save variables to an output file (ntuple)
131 ma.variablesToNtuple(
132  "B0",
133  variables=b_vars,
134  filename="Bd2JpsiKS.root",
135  treename="tree",
136  path=main,
137 )
138 
139 # Start the event loop (actually start processing things)
140 b2.process(main)
141 
142 # print out the summary
143 print(b2.statistics)
def stdKshorts(prioritiseV0=True, fitter='TreeFit', path=None, updateAllDaughters=False, writeOut=False)
Definition: stdV0s.py:17