Top quark pair production at the LHC, with all hadronic resolved decays for solving event combinatorics

<p><strong>R&amp;D Datasets for solving event combinatorics in all hadronic top quark pair events at the LHC.</strong></p> <p>Used in the development of Topographs: Topological Reconstruction of Particle Physics Processes using Graph Neural Networks</p> <p>&nbsp;</p> <p>The datasets contain 5.8M ttbar events in the all hadronic decay channel, with jets matched to the truth partons in the top quark decays.</p> <p>&nbsp;</p> <p><strong>Event generation</strong></p> <ul> <li>Centre of Mass energy: 13 TeV</li> <li>MC Generator: MadGraph5_aMC@NLO v3.1.0, with MadSpin modelling the decays of the top quarks and W bosons.</li> <li>Parton Shower: Pythia v .243</li> <li>Detector response: Delphes v3.4.2 using ATLAS-like geometry</li> <li>Jets reconstructed with anti-kt algorithm, R=0.4, using FastJet</li> <li>b-Tagging corresponds to inclusive 70% b-jet efficiency</li> </ul> <p><strong>Event selection and truth matching</strong></p> <ul> <li>All events are required to have at least six reconstructed jets and exactly zero leptons (electrons or muons)</li> <li>Partons are matched to jets using <span class="math-tex">\(\Delta R\)</span> matching, with <span class="math-tex">\(\Delta R &lt; 0.4\)</span></li> <li>Events with partons matched to multiple jets or jets to multiple partons are discarded</li> <li>Up to 16 jets are stored per event</li> </ul> <p>In the training dataset 1,340,000 events have all partons from the ttbar decays matched to jets.</p> <p>In the validation dataset, 71,000 events have all partons from the ttbar decays matched to jets.</p> <p>In the testing dataset 76,000 events have all partons from the ttbar decays matched to jets.</p> <p><strong>Dataset format</strong></p> <p>The dataset is in h5 format and the key &#39;delphes&#39; has the following numpy arrays:</p> <pre><code>jets (16), jets_indices (16), matchability, nbjets, njets, partons (10) </code></pre> <p>Jets structured numpy array per event:</p> <ul> <li> <pre><code>(pt, eta, phi, energy, is_tagged)</code></pre> </li> </ul> <p>Jets_indices:</p> <ul> <li>Integer corresponding to the parton the jet is matched to</li> <li>From 0 to 5: b1 W1j1 W1j2 b2 W2j1 W2j2 (1= from top, 2=from antitop)</li> <li>-1 indicates not matched to a parton</li> <li>Properties of matched partons can be obtained from the partons array</li> </ul> <p>matchability:</p> <ul> <li>Which partons are matched to jets in event</li> <li>Binary representation with bits corresponding to each parton (length 6) 0b111111</li> <li>From left to right: b1 W1j1 W1j2 b2 W2j1 W2j2</li> <li>0b111000 (56) is one top fully matched, 0b000111 (7) is the other top fully matched, 0b111111 (63) is both tops fully matched</li> </ul> <p>njets, nbjets:</p> <ul> <li>How many jets/bjets in event</li> </ul> <p>partons:</p> <ul> <li>List of truth particles from ttbar decay: tops, Ws, quarks, ordered by top quark and its decays followed by anti-top and its decays</li> <li> <pre><code>PDGID, pt, eta, phi, mass</code></pre> </li> </ul> <p>&nbsp;</p> <p>&nbsp;</p> <p>&nbsp;</p>