Lepton-mass effects in the decays $H\to Z{Z}^{\ast }\to {\ell }^{+}{\ell }^{-}{\tau }^{+}{\tau }^{-}$ and $H\to W{W}^{\ast }\to \ell \nu \tau {\nu }_{\tau }$

Abstract

We consider lepton-mass effects in the cascade decays $H\to Z(\to {\ell }^{+}{\ell }^{-})+Z^{\ast }(\to {\tau }^{+}{\tau }^{-})$ and $H\to W^{-}(\to {\ell }^{-}{\bar{\nu }}_{\ell })+W^{+\ast }(\to {\tau }^{+}{\nu }_{\tau })$. Since the scale of the problem is set by the off-shellness $q^2$ of the respective gauge bosons in the limits $(m_{\ell }+m_{{\ell }^{\prime }}{)}^2\le q^2\le (m_H-m_{W,Z}{)}^2$ and not by $m_{W,Z}^2$, lepton-mass effects are non-negligible for the $\tau$ modes in particular close to the threshold of the off-shell decays. Lepton-mass effects show up e.g.\ in the three-fold joint angular decay distribution for the decays. Nonzero lepton masses lead to leptonic helicity-flip contributions which in turn can generate novel angular dependencies in the respective three-fold angular decay distributions. Lepton-mass effects are more pronounced in the $H\to Z(\to \ell \ell )Z^{\ast }(\to \tau \tau )$ mode which, in part, is due to the fact that the ratio of lepton helicity flip/nonflip contributions in the decay $Z^{\ast }\to {\ell }^{+}{\ell }^{-}$ is four times larger than in the decay $W^{+\ast }\to {\ell }^{+}\nu$. We also briefly consider the corresponding off-shell -- off-shell decays $H\to Z^{\ast }(\to {\ell }^{+}{\ell }^{-})+Z^{\ast }(\to {\tau }^{+}{\tau }^{-})$ and $H\to W^{-\ast }(\to {\ell }^{-}{\bar{\nu }}_{\ell })+W^{+\ast }(\to {\tau }^{+}{\nu }_{\tau })$.

arXiv comment45 pages, 9 figures and 6 tables, published version

References in corpus (30)

• 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
• Evidence for the spin-0 nature of the Higgs boson using ATLAS data
• Measurement of the properties of a Higgs boson in the four-lepton final state
• Study of the mass and spin-parity of the Higgs boson candidate via its decays to Z boson pairs
• Spin determination of single-produced resonances at hadron colliders
• Precise predictions for the Higgs-boson decay H -> W W/Z Z -> 4 leptons
• On the spin and parity of a single-produced resonance at the LHC
• Standard Model Higgs-Boson Branching Ratios with Uncertainties
• Radiative corrections to the semileptonic and hadronic Higgs-boson decays H -> W W/Z Z -> 4 fermions
• Identifying the Higgs Spin and Parity in Decays to Z Pairs
• Higgs look-alikes at the LHC
• The semileptonic decay Lambda_b -> Lambda_c + tau(-) + antinu_tau in the covariant confined quark model
• Helicity Analysis of Semileptonic Hyperon Decays Including Lepton Mass Effects
• Beyond Geolocating: Constraining Higher Dimensional Operators in $H\to 4\ell$ with Off-Shell Production and More
• Precision studies of the Higgs boson decay channel H -> ZZ -> 4l with MEKD
• Anomalous Higgs couplings in angular asymmetries of H --> Zl+l- and e+e- --> HZ
• Nonstandard Higgs Couplings from Angular Distributions in $h\to Z{\ell }^{+}{\ell }^{-}$
• The $h\to 4\ell$ spectrum at low $m_{34}$: Standard Model vs. light New Physics
• Inferring the nature of the boson at 125-126 GeV
• W-propagator corrections to muon and tau leptonic decays
• Determination of spin and parity of the Higgs boson in the $W{W}^{\ast }\to e\nu \mu \nu$ decay channel with the ATLAS detector
• CP mixed property of the Higgs-like particle in the decay channel $h\to Z{Z}^{\ast }\to 4l$
• K^+ -> pi^+pi^0e^+e^-: a novel short-distance probe
• Low-mass Higgs decays to four leptons at one loop and beyond
• Leptonic $\mu$- and $\tau$-decays: mass effects, polarization effects and $O(\alpha )$ radiative corrections
• O(α_s) corrections to the decays of polarized W^+- and Z bosons into massive quark pairs
• Different approaches to calculate the $K^{\pm }\to {\pi }^{\pm }{\pi }^0{e}^{+}{e}^{-}$ decay width
• Fully analytical O(α_s) results for on-shell and off-shell polarized W-boson decays into massive quark pairs

Cited by in corpus (11)

• Bell inequalities and quantum entanglement in weak gauge bosons production at the LHC and future colliders
• Exclusive decays $B\to {\ell }^{-}\bar{\nu }$ and $B\to D^{(\ast )}{\ell }^{-}\bar{\nu }$ in the covariant quark model
• Laboratory-frame tests of quantum entanglement in $H\to WW$
• Precision calculations for h->WW/ZZ->4 fermions in the Two-Higgs-Doublet Model with PROPHECY4F
• Vector boson polarizations in the decay of the Standard Model Higgs
• Polarized Z bosons from the decay of a Higgs boson produced in association with two jets at the LHC
• A new evaluation of the $HZZ$ coupling: direct bounds on anomalous contributions and $CP$ violating effects via a new asymmetry
• Polarized and unpolarized off-shell $H^{\ast }\to ZZ\to 4\ell$ decay above the $2m_Z$ threshold
• Gauge dependence of the gauge boson projector
• The Higgs boson decay into ZZ decaying to identical fermion pairs
• NLO EW and QCD corrections to polarized ZZ production in the four-charged-lepton channel at the LHC