Potential for optimizing Higgs boson CP measurement in H to tau tau decay at LHC and ML techniques

Abstract

We investigate potential for measuring CP state of the Higgs boson in the H to tau tau$ decay with consecutive tau-lepton decays in channels: tau^+- to rho^+- nu_tau and tau^+- to a1^+- nu_tau combined. Subsequent decays rho^+- to pi^+- pi^0, a1^+- to rho^0 pi^+- and rho^0 to pi^+ pi^- are taken into account. We will explore extensions of the method, where acoplanarity angle for the planes build on the visible decay products, pi^+- pi^0 of tau^+- to pi^pm pi^0 nu_tau, was used. The angle is sensitive to transverse spin correlations, thus to parity. We show, that in the case of the cascade decays of tau to a1 nu, information on the CP state of Higgs can be extracted from the acoplanarity angles as well. Because in the cascade decay a1^+- to rho^0 pi^pm,rho^0 to pi^+ pi^- up to four planes can be defined, up to 16 distinct acoplanarity angles are available for H \to tau tau to a1^+ a1^- nu nu decays. These acoplanarities carry in part supplementary but also correlated information. It is thus cumbersome to evaluate an overall sensitivity. We investigate sensitivity potential of such analysis, by developing and implementing model in the Machine Learning (ML) techniques. We quantify possible improvements when multi-dimensional phase-space of outgoing decay products directions is used, instead of 1-dimensional projections i.e. the acoplanarity angles. We do not take into account ambiguities resulting from detector uncertainties or background contamination, we concentrate on usefulness of ML methods and tau to 3pi nu decays for Higgs boson parity measurement.

arXiv comment1+14 pages,7 figures

References in corpus (23)

• Adam: A Method for Stochastic Optimization
• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• Combined Measurement of the Higgs Boson Mass in $pp$ Collisions at $\sqrt{s}=7$ and 8 TeV with the ATLAS and CMS Experiments
• Measurements of the Higgs boson production and decay rates and constraints on its couplings from a combined ATLAS and CMS analysis of the LHC $pp$ collision data at $\sqrt{s}=$ 7 and 8 TeV
• LHCb Detector Performance
• Evidence for the spin-0 nature of the Higgs boson using ATLAS data
• Constraints on the spin-parity and anomalous HVV couplings of the Higgs boson in proton collisions at 7 and 8 TeV
• Study of the spin and parity of the Higgs boson in diboson decays with the ATLAS detector
• Universal Interface of TAUOLA Technical and Physics Documentation
• Performance of tau-lepton reconstruction and identification in CMS
• Prospects of Measuring the Parity of Higgs Particles
• How to pin down the CP quantum numbers of a Higgs boson in its tau decays at the LHC
• Reconstruction of hadronic decay products of tau leptons with the ATLAS experiment
• Determining the CP parity of Higgs bosons at the LHC in the $\tau$ to 1-prong decay channels
• Measuring the Higgs boson's parity using tau --> rho nu
• Probing the CP nature of the Higgs boson at linear colliders with tau spin correlations; the case of mixed scalar--pseudoscalar couplings
• Higgs CP properties using the tau decay modes at the ILC
• Prospects of constraining the Higgs CP nature in the tau decay channel at the LHC
• Determination of the Higgs CP mixing angle in the tau decay channels at the LHC including the Drell-Yan background
• Measuring the Higgs boson parity at a Linear Collider using the tau impact parameter and tau --> rho nu decay
• CP violation in a light Higgs boson decay from tau-spin correlations at a linear collider
• TauSpinner: a tool for simulating CP effects in H to tau tau decays at LHC

Cited by in corpus (15)

• Two-Higgs-Doublet Model with Soft CP-violation Confronting Electric Dipole Moments and Colliders
• Multi-photon Monte Carlo event generator KKMCee for lepton and quark pair production in lepton colliders
• Measurement of the $CP$ properties of Higgs boson interactions with $\tau$-leptons with the ATLAS detector
• Deep learning approach to the Higgs boson CP measurement in H to tau tau decay and associated systematics
• Documentation of TauSpinner algorithms -- program for simulating spin effects in tau-lepton production at LHC
• Deep Neural Network application: Higgs boson CP state mixing angle in H to tau tau decay and at LHC
• Machine learning classification: case of Higgs boson CP state in H to tau tau decay at LHC
• Monte Carlo, fitting and Machine Learning for Tau leptons
• Signal mixture estimation for degenerate heavy Higgses using a deep neural network
• Measurement of the Higgs Boson Couplings and CP Structure Using Tau Leptons at the LHC
• LHC Higgs CP Sensitive Observables in H to tau^+ tau^-; tau^pm to (3pi)^pm nu and Machine Learning Benefits
• A multi-instance deep neural network classifier: application to Higgs boson CP measurement
• Testing CP-violation in a Heavy Higgs Sector at CLIC
• Automated calculation of matrix elements and physics motivated observables
• Tau lepton production and decays: perspective of multi-dimensional distributions and Monte Carlo methods