This study explores the production of charged Higgs particles through photon-photon collisions within the context of the Two Higgs Doublet Model,including one-loop-level scattering amplitudes of electroweak and QED ra...This study explores the production of charged Higgs particles through photon-photon collisions within the context of the Two Higgs Doublet Model,including one-loop-level scattering amplitudes of electroweak and QED radiation.The cross-section has been scanned for the plane(m_(φ^(0)),√s)to investigate the process ofγγ→H^(+)H^(-).Three particular numerical scenarios,i.e.,low-,non-alignment,and short-cascade are employed.The decay channels for charged Higgs particles are examined using h^(0)for low-m_(H^(0))and H^(0)for non-alignment and short-cascade scenarios incorporating the new experimental and theoretical constraints along with the analysis for cross-sections.We find that,at a low energy,the cross-section is consistently higher for all scenarios.However,as√s increases,it reaches a peak value at 1 TeV for all benchmark scenarios.The branching ratio of the decay channels indicates that for non-alignment,the mode of decay W^(±)h^(0)takes control,and for a short cascade,the prominent decay mode remains tb,whereas in the low-scenario,the dominant decay channel is of W^(±)h^(0).In our research,we employ contemporary machine-learning methodologies to investigate the production of high-energy Higgs bosons within a 3.0 TeVγγcollider.We have used multivariate approaches such as Boosted Decision Trees(BDT),LikelihoodD,and Multilayer Perceptron(MLP)to show the observability of heavy-charged Higgs Bosons versus the most significant Standard Model backgrounds.The purity of the signal efficiency and background rejection are measured for each cut value.展开更多
Recently,the experimental measurements of the branching ratios and different polarization asymmetries for processes occurring through flavor-changing-charged current(b→cτν¯_(τ))transitions by BABAR,Belle,and ...Recently,the experimental measurements of the branching ratios and different polarization asymmetries for processes occurring through flavor-changing-charged current(b→cτν¯_(τ))transitions by BABAR,Belle,and LHCb have revealed some significant differences from the corresponding Standard Model(SM)predictions.This has triggered an interest to search for physics beyond the SM in the context of various new physics(NP)models and using the model-independent weak effective Hamiltonian(WEH).Assuming left-handed neutrinos,we add the dimension-six vector,(pseudo-)scalar,and tensor operators with complex Wilson coefficients(WCs)to the SM WEH.Using 60%,30%,and 10%constraints resulting from the branching ratio of B_(c)→τν¯_(τ),we reassess the parametric space of these new physics WCs accommodating the current anomalies based on the most recent HFLAV data of R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*))and Belle data of F_(L)(D^(*))and P_(τ)(D^(*)).We find that the allowed parametric region of left-handed scalar couplings strongly depends on the constraints of the B_(c)→τν¯_(τ)branching ratio,and the maximum pull from the SM predictions results from the<60%branching ratio limit.Also,the parametric region changes significantly if we extend the analysis by adding LHCb data of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(Λ_(c)).Furthermore,due to the large uncertainties in the measurements of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(X_(c)),we derive the sum rules which complement them with R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*)).Using the best-fit points of the new complex WCs along with the latest measurements of R_(τ/μ,e)(D(^(*))),we predict the numerical values of the observable R_(τ/ℓ)(Λ_(c)),R_(τ/μ)(J/ψ),and R_(τ/ℓ)(X_(c))from the sum rules.The simultaneous dependence of abovementioned physical observables on the NP WCs is established by plotting their correlation with R_(D) and R_(D^(*)),which are useful to discriminate between various NP scenarios.We find that the most significant impact of NP results from the WC C^(S)_(L)=4C^(T).Finally,we study the impact of these NP couplings on various angular and CP triple product asymmetries that could be measured in some ongoing and future experiments.The precise measurements of these observables are important to check the SM and extract the possible NP.展开更多
基金Supported by the Simons Foundation and member institutions。
文摘This study explores the production of charged Higgs particles through photon-photon collisions within the context of the Two Higgs Doublet Model,including one-loop-level scattering amplitudes of electroweak and QED radiation.The cross-section has been scanned for the plane(m_(φ^(0)),√s)to investigate the process ofγγ→H^(+)H^(-).Three particular numerical scenarios,i.e.,low-,non-alignment,and short-cascade are employed.The decay channels for charged Higgs particles are examined using h^(0)for low-m_(H^(0))and H^(0)for non-alignment and short-cascade scenarios incorporating the new experimental and theoretical constraints along with the analysis for cross-sections.We find that,at a low energy,the cross-section is consistently higher for all scenarios.However,as√s increases,it reaches a peak value at 1 TeV for all benchmark scenarios.The branching ratio of the decay channels indicates that for non-alignment,the mode of decay W^(±)h^(0)takes control,and for a short cascade,the prominent decay mode remains tb,whereas in the low-scenario,the dominant decay channel is of W^(±)h^(0).In our research,we employ contemporary machine-learning methodologies to investigate the production of high-energy Higgs bosons within a 3.0 TeVγγcollider.We have used multivariate approaches such as Boosted Decision Trees(BDT),LikelihoodD,and Multilayer Perceptron(MLP)to show the observability of heavy-charged Higgs Bosons versus the most significant Standard Model backgrounds.The purity of the signal efficiency and background rejection are measured for each cut value.
文摘Recently,the experimental measurements of the branching ratios and different polarization asymmetries for processes occurring through flavor-changing-charged current(b→cτν¯_(τ))transitions by BABAR,Belle,and LHCb have revealed some significant differences from the corresponding Standard Model(SM)predictions.This has triggered an interest to search for physics beyond the SM in the context of various new physics(NP)models and using the model-independent weak effective Hamiltonian(WEH).Assuming left-handed neutrinos,we add the dimension-six vector,(pseudo-)scalar,and tensor operators with complex Wilson coefficients(WCs)to the SM WEH.Using 60%,30%,and 10%constraints resulting from the branching ratio of B_(c)→τν¯_(τ),we reassess the parametric space of these new physics WCs accommodating the current anomalies based on the most recent HFLAV data of R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*))and Belle data of F_(L)(D^(*))and P_(τ)(D^(*)).We find that the allowed parametric region of left-handed scalar couplings strongly depends on the constraints of the B_(c)→τν¯_(τ)branching ratio,and the maximum pull from the SM predictions results from the<60%branching ratio limit.Also,the parametric region changes significantly if we extend the analysis by adding LHCb data of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(Λ_(c)).Furthermore,due to the large uncertainties in the measurements of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(X_(c)),we derive the sum rules which complement them with R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*)).Using the best-fit points of the new complex WCs along with the latest measurements of R_(τ/μ,e)(D(^(*))),we predict the numerical values of the observable R_(τ/ℓ)(Λ_(c)),R_(τ/μ)(J/ψ),and R_(τ/ℓ)(X_(c))from the sum rules.The simultaneous dependence of abovementioned physical observables on the NP WCs is established by plotting their correlation with R_(D) and R_(D^(*)),which are useful to discriminate between various NP scenarios.We find that the most significant impact of NP results from the WC C^(S)_(L)=4C^(T).Finally,we study the impact of these NP couplings on various angular and CP triple product asymmetries that could be measured in some ongoing and future experiments.The precise measurements of these observables are important to check the SM and extract the possible NP.
