Documentation of TauSpinner algorithms -- program for simulating spin effects in tau-lepton production at LHC

Abstract

The tau-lepton plays an important role in the physics program at the Large Hadron Collider (LHC). It offers a probe in searches for New Physics and to measure parameters of the Standard Model. Spin of tau lepton is an interesting phenomenological quantity for separation of signal from background or in measuring properties of particles. A proper treatment of tau spin effects in the Monte Carlo simulations is important for understanding the detector acceptance as well as for the measurements/use of tau polarization and tau spin correlations. The TauSpinner is a tool to modify tau$spin effects in any sample. Also production matrix elements can be modified with its help. The general principle of TauSpinner algorithm rely on the kinematic of outgoing particles (or jets) only, and to average over all possible initial states accordingly to assumed parton distributions and cross-sections. Incoming on mass-shell parton four-momenta are reconstructed in approximation, but energy-momentum conservation is obeyed. Samples of events featuring tau leptons with their decay products, can be used as an input. The information on the polarization and spin correlations, and production/decay matrix elements is reconstructed from the kinematics of the tau lepton(s) (also nu_tau in case of W-mediated processes) and tau decay products (also jets). No other information is required. By calculating spin (or production/decay matrix element) weights, attributed to each event, it enables evaluation of modifications without regenerating events. Elements of program functionalities together with explanation of the use are given in Appendices. Present publication collect program documentation, previously scattered over several publiications.

arXiv comment1+24 pages

References in corpus (33)

• An Introduction to PYTHIA 8.2
• Event generation with SHERPA 1.1
• Herwig 7.0 / Herwig++ 3.0 Release Note
• The Precision Monte Carlo Event Generator KK For Two-Fermion Final States In e+e- Collisions
• General-purpose event generators for LHC physics
• A standard format for Les Houches Event Files
• Evidence for the Higgs-boson Yukawa coupling to tau leptons with the ATLAS detector
• Universal Interface of TAUOLA Technical and Physics Documentation
• Search for neutral Higgs bosons of the minimal supersymmetric standard model in pp collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
• SANCscope -- v.1.00
• Reweighting Parton Showers
• Search for Minimal Supersymmetric Standard Model Higgs bosons $H/A$ and for a $Z^{\prime }$ boson in the $\tau \tau$ final state produced in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS Detector
• Global Positioning of Spin GPS Scheme for Half-Spin Massive Spinors
• A search for high-mass resonances decaying to ${\tau }^{+}{\tau }^{-}$ in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
• TauSpinner program for studies on spin effect in tau production at the LHC
• Standard SANC Modules
• MC-TESTER: a universal tool for comparisons of Monte Carlo predictions for particle decays in high energy physics
• Ascertaining the spin for new resonances decaying into tau+ tau- at Hadron Colliders
• Measurement of tau polarization in W->taunu decays with the ATLAS detector in pp collisions at sqrt(s) = 7 TeV
• Potential for optimizing Higgs boson CP measurement in H to tau tau decay at LHC and ML techniques
• Measurement of the $\mathrm{Z}{\gamma }^{\ast }\to \tau \tau$ cross section in pp collisions at $\sqrt{s}=$ 13 TeV and validation of $\tau$ lepton analysis techniques
• Matching NLO parton shower matrix element with exact phase space: case of W -> l nu (gamma) and gamma^* -> pi^+pi^-(gamma)
• Deep learning approach to the Higgs boson CP measurement in H to tau tau decay and associated systematics
• MC-TESTER v. 1.23: a universal tool for comparisons of Monte Carlo predictions for particle decays in high energy physics
• TauSpinner: a tool for simulating CP effects in H to tau tau decays at LHC
• Search for squarks and gluinos in events with hadronically decaying tau leptons, jets and missing transverse momentum in proton-proton collisions at $\sqrt{s}=13$ TeV recorded with the ATLAS detector
• Application of TauSpinner for studies on tau-lepton polarization and spin correlations in Z, W and H decays at LHC
• Tau Decays in Pythia 8
• Separating Electroweak and Strong interactions in Drell-Yan processes at LHC: leptons angular distributions and reference frames
• Measurement of $\tau$ polarisation in $Z/{\gamma }^{\ast }\to \tau \tau$ decays in proton-proton collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
• Production of tau tau jj final states at the LHC and the TauSpinner algorithm: the spin-2 case
• W production at LHC: lepton angular distributions and reference frames for probing hard QCD
• Production of tau lepton pairs with high pT jets at the LHC and the TauSpinner reweighting algorithm

Cited by in corpus (10)

• Analysis of the CP structure of the Yukawa coupling between the Higgs boson and $\tau$ leptons in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Search for charged-lepton-flavour violation in $Z$-boson decays with the ATLAS detector
• Search for lepton-flavor-violation in $Z$-boson decays with $\tau$-leptons with the ATLAS detector
• Measurement of the $CP$ properties of Higgs boson interactions with $\tau$-leptons with the ATLAS detector
• EasyScan_HEP: a tool for connecting programs to scan the parameter space of physics models
• Deep Neural Network application: Higgs boson CP state mixing angle in H to tau tau decay and at LHC
• Electron-positron, parton-parton and photon-photon production of $\tau$-lepton pairs: anomalous magnetic and electric dipole moments spin effects
• Spin correlations in $\tau$-lepton pair production due to anomalous magnetic and electric dipole moments
• The TauSpinner approach for electroweak corrections in LHC Z to ll observables
• Monte Carlo Event Generator updates, for tau pair events at Belle II energies