#!/usr/bin/env python # coding: utf-8 # # df105_WBosonAnalysis # The W boson mass analysis from the ATLAS Open Data release of 2020, with RDataFrame. # # This tutorial is the analysis of the W boson mass taken from the ATLAS Open Data release in 2020 # (http://opendata.atlas.cern/release/2020/documentation/). The data was recorded with the ATLAS detector # during 2016 at a center-of-mass energy of 13 TeV. W bosons are produced frequently at the LHC and # are an important background to studies of Standard Model processes, for example the Higgs boson analyses. # # The analysis is translated to a RDataFrame workflow processing up to 60 GB of simulated events and data. # By default the analysis runs on a preskimmed dataset to reduce the runtime. The full dataset can be used with # the --full-dataset argument and you can also run only on a fraction of the original dataset using the argument --lumi-scale. # # See the [corresponding spec json file](https://github.com/root-project/root/blob/master/tutorials/analysis/dataframe/df105_WBosonAnalysis.json). # # # # # **Author:** Stefan Wunsch (KIT, CERN) # This notebook tutorial was automatically generated with ROOTBOOK-izer from the macro found in the ROOT repository on Wednesday, May 14, 2025 at 04:42 PM. # In[1]: import ROOT import sys import json import argparse import os # Argument parsing # In[2]: parser = argparse.ArgumentParser() parser.add_argument("--lumi-scale", type=float, default=0.001, help="Run only on a fraction of the total available 10 fb^-1 (only usable together with --full-dataset)") parser.add_argument("--full-dataset", action="store_true", default=False, help="Use the full dataset (use --lumi-scale to run only on a fraction of it)") parser.add_argument("-b", action="store_true", default=False, help="Use ROOT batch mode") parser.add_argument("-t", action="store_true", default=False, help="Use implicit multi threading (for the full dataset only possible with --lumi-scale 1.0)") if 'df105_WBosonAnalysis.py' in sys.argv[0]: # Script args = parser.parse_args() else: # Notebook args = parser.parse_args(args=[]) if args.b: ROOT.gROOT.SetBatch(True) if args.t: ROOT.EnableImplicitMT() if not args.full_dataset: lumi_scale = 0.001 # The preskimmed dataset contains only 0.01 fb^-1 else: lumi_scale = args.lumi_scale lumi = 10064.0 print('Run on data corresponding to {:.2f} fb^-1 ...'.format(lumi * lumi_scale / 1000.0)) if args.full_dataset: dataset_path = "root://eospublic.cern.ch//eos/opendata/atlas/OutreachDatasets/2020-01-22" else: dataset_path = "root://eospublic.cern.ch//eos/root-eos/reduced_atlas_opendata/w" # Create a ROOT dataframe for each dataset # Note that we load the filenames from the external json file placed in the same folder than this script. # In[3]: files = json.load(open(os.path.join(ROOT.gROOT.GetTutorialsDir(), "analysis/dataframe/df105_WBosonAnalysis.json"))) processes = files.keys() df = {} xsecs = {} sumws = {} samples = [] for p in processes: for d in files[p]: # Construct the dataframes folder = d[0] # Folder name sample = d[1] # Sample name xsecs[sample] = d[2] # Cross-section sumws[sample] = d[3] # Sum of weights num_events = d[4] # Number of events samples.append(sample) df[sample] = ROOT.RDataFrame("mini", "{}/1lep/{}/{}.1lep.root".format(dataset_path, folder, sample)) # Scale down the datasets if requested if args.full_dataset and lumi_scale < 1.0: df[sample] = df[sample].Range(int(num_events * lumi_scale)) # Select events for the analysis # Just-in-time compile custom helper function performing complex computations # In[4]: ROOT.gInterpreter.Declare(""" bool GoodElectronOrMuon(int type, float pt, float eta, float phi, float e, float trackd0pv, float tracksigd0pv, float z0) { ROOT::Math::PtEtaPhiEVector p(pt / 1000.0, eta, phi, e / 1000.0); if (abs(z0 * sin(p.theta())) > 0.5) return false; if (type == 11 && abs(eta) < 2.46 && (abs(eta) < 1.37 || abs(eta) > 1.52)) { if (abs(trackd0pv / tracksigd0pv) > 5) return false; return true; } if (type == 13 && abs(eta) < 2.5) { if (abs(trackd0pv / tracksigd0pv) > 3) return false; return true; } return false; } """) for s in samples: # Select events with a muon or electron trigger and with a missing transverse energy larger than 30 GeV df[s] = df[s].Filter("trigE || trigM")\ .Filter("met_et > 30000") # Find events with exactly one good lepton df[s] = df[s].Define("good_lep", "lep_isTightID && lep_pt > 35000 && lep_ptcone30 / lep_pt < 0.1 && lep_etcone20 / lep_pt < 0.1")\ .Filter("ROOT::VecOps::Sum(good_lep) == 1") # Apply additional cuts in case the lepton is an electron or muon df[s] = df[s].Define("idx", "ROOT::VecOps::ArgMax(good_lep)")\ .Filter("GoodElectronOrMuon(lep_type[idx], lep_pt[idx], lep_eta[idx], lep_phi[idx], lep_E[idx], lep_trackd0pvunbiased[idx], lep_tracksigd0pvunbiased[idx], lep_z0[idx])") # Apply luminosity, scale factors and MC weights for simulated events # In[5]: for s in samples: if "data" in s: df[s] = df[s].Define("weight", "1.0") else: df[s] = df[s].Define("weight", "scaleFactor_ELE * scaleFactor_MUON * scaleFactor_LepTRIGGER * scaleFactor_PILEUP * mcWeight * {} / {} * {}".format(xsecs[s], sumws[s], lumi)) # Compute transverse mass of the W boson using the lepton and the missing transverse energy and make a histogram # In[6]: ROOT.gInterpreter.Declare(""" float ComputeTransverseMass(float met_et, float met_phi, float lep_pt, float lep_eta, float lep_phi, float lep_e) { ROOT::Math::PtEtaPhiEVector met(met_et, 0, met_phi, met_et); ROOT::Math::PtEtaPhiEVector lep(lep_pt, lep_eta, lep_phi, lep_e); return (met + lep).Mt() / 1000.0; } """) histos = {} for s in samples: df[s] = df[s].Define("mt_w", "ComputeTransverseMass(met_et, met_phi, lep_pt[idx], lep_eta[idx], lep_phi[idx], lep_E[idx])") histos[s] = df[s].Histo1D(ROOT.RDF.TH1DModel(s, "mt_w", 24, 60, 180), "mt_w", "weight") # Run the event loop and merge histograms of the respective processes # RunGraphs allows to run the event loops of the separate RDataFrame graphs # concurrently. This results in an improved usage of the available resources # if each separate RDataFrame can not utilize all available resources, e.g., # because not enough data is available. # In[7]: ROOT.RDF.RunGraphs([histos[s] for s in samples]) def merge_histos(label): h = None for i, d in enumerate(files[label]): t = histos[d[1]].GetValue() if i == 0: h = t.Clone() else: h.Add(t) h.SetNameTitle(label, label) return h data = merge_histos("data") wjets = merge_histos("wjets") zjets = merge_histos("zjets") ttbar = merge_histos("ttbar") diboson = merge_histos("diboson") singletop = merge_histos("singletop") # Create the plot # Set styles # In[8]: ROOT.gROOT.SetStyle("ATLAS") # Create canvas # In[9]: c = ROOT.TCanvas("c", "", 600, 600) c.SetTickx(0) c.SetTicky(0) c.SetLogy() # Draw stack with MC contributions # In[10]: stack = ROOT.THStack() for h, color in zip( [singletop, diboson, ttbar, zjets, wjets], [(0.82, 0.94, 0.76), (0.76, 0.54, 0.57), (0.61, 0.6, 0.8), (0.97, 0.81, 0.41), (0.87, 0.35, 0.42)]): h.SetLineWidth(1) h.SetLineColor("black") h.SetFillColor(ROOT.TColor.GetColor(*color)) # From Python 3.11 onward, implicit conversion of the tuple works too: # h.SetFillColor(color) stack.Add(h) stack.Draw("HIST") stack.GetXaxis().SetLabelSize(0.04) stack.GetXaxis().SetTitleSize(0.045) stack.GetXaxis().SetTitleOffset(1.3) stack.GetXaxis().SetTitle("m_{T}^{W#rightarrow l#nu} [GeV]") stack.GetYaxis().SetTitle("Events") stack.GetYaxis().SetLabelSize(0.04) stack.GetYaxis().SetTitleSize(0.045) stack.SetMaximum(1e10 * args.lumi_scale) stack.SetMinimum(1) # Draw data # In[11]: data.SetMarkerStyle(20) data.SetMarkerSize(1.2) data.SetLineWidth(2) data.SetLineColor("black") data.Draw("E SAME") # Add legend # In[12]: legend = ROOT.TLegend(0.60, 0.65, 0.92, 0.92) legend.SetTextFont(42) legend.SetFillStyle(0) legend.SetBorderSize(0) legend.SetTextSize(0.04) legend.SetTextAlign(32) legend.AddEntry(data, "Data" ,"lep") legend.AddEntry(wjets, "W+jets", "f") legend.AddEntry(zjets, "Z+jets", "f") legend.AddEntry(ttbar, "t#bar{t}", "f") legend.AddEntry(diboson, "Diboson", "f") legend.AddEntry(singletop, "Single top", "f") legend.Draw() # Add ATLAS label # In[13]: text = ROOT.TLatex() text.SetNDC() text.SetTextFont(72) text.SetTextSize(0.045) text.DrawLatex(0.21, 0.86, "ATLAS") text.SetTextFont(42) text.DrawLatex(0.21 + 0.16, 0.86, "Open Data") text.SetTextSize(0.04) text.DrawLatex(0.21, 0.80, "#sqrt{{s}} = 13 TeV, {:.2f} fb^{{-1}}".format(lumi * args.lumi_scale / 1000.0)) # Save the plot # In[14]: c.SaveAs("df105_WBosonAnalysis.png") print("Saved figure to df105_WBosonAnalysis.png") # Draw all canvases # In[15]: from ROOT import gROOT gROOT.GetListOfCanvases().Draw()