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 ( $m_{\phi^{0}}, \sqrt{s}$ ) to investigate the process of $\gamma\gamma \rightarrow H^{+}H^{-}$ . Three particular numerical scenarios, $\textit{i.e}$., low- $m_{H}$ , 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 $\sqrt{s}$ 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 $W^{\pm} h^{0}$ takes control, and for a short cascade, the prominent decay mode remains $t\overline {b}$ , whereas in the low- $m_{H}$ scenario, the dominant decay channel is of $W^{\pm} h^{0}$ . In our research, we employ contemporary machine-learning methodologies to investigate the production of high-energy Higgs bosons within a 3.0 TeV $\gamma\gamma$ collider. 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.

Ijaz Ahmed

Abdul Quddus

Jamil Muhammad

Pakistan

Muhammad Shoaib

Saba Shafaq

Probing heavy charged Higgs bosons at gamma-gamma colliders using a multivariate technique * Supported by the Simons Foundation and member institutions

Recently, the experimental measurements of the branching ratios and different polarization asymmetries for processes occurring through flavor-changing-charged current   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $  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\rightarrow c\tau\overline{\nu}_{\tau}) $  , we reassess the parametric space of these new physics WCs accommodating the current anomalies based on the most recent HFLAV data of   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   and   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   and Belle data of   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   and   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $  . We find that the allowed parametric region of left-handed scalar couplings strongly depends on the constraints of the   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   branching ratio, and the maximum pull from the SM predictions results from the &lt;60% branching ratio limit. Also, the parametric region changes significantly if we extend the analysis by adding LHCb data of   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   and   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $  . Furthermore, due to the large uncertainties in the measurements of   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   and   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $  , we derive the sum rules which complement them with   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   and   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $  . Using the best-fit points of the new complex WCs along with the latest measurements of   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $  , we predict the numerical values of the observable   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $  ,   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   , and   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   from the sum rules. The simultaneous dependence of abovementioned physical observables on the NP WCs is established by plotting their correlation with   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   and   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $  , which are useful to discriminate between various NP scenarios. We find that the most significant impact of NP results from the WC   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $  . Finally, we study the impact of these NP couplings on various angular and   $ (b\rightarrow c\tau\overline{\nu}_{\tau}) $   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.

Muhammad Arslan

Tahira Yasmeen

Ishtiaq Ahmed

Muhammad Jamil Aslam

Analysis of anomalies using weak effective Hamiltonian with complex couplings and their impact on various physical observables

Abstract Experimental studies of the observables associated with  transitions in semileptonic B-meson decays at BaBar, Belle, and LHCb have shown some deviations from the Standard Model predictions, consequently providing a handy tool to probe the possible new physics (NP). In this context, we first revisit the impact of recent measurements of  and  on the parametric space of the NP scenarios. In addition, we include the  data in the analysis and find that their influence on the best-fit point and the parametric space is mild. Using the recent HFLAV data, after validating the well established sum rule of , we derive a similar sum rule for . Furthermore, according to the updated data, we modify the correlation among the different observables, giving us their interesting interdependence. Finally, to discriminate the various NP scenarios, we plot the different angular observables and their ratios for  against the transfer momentum square , using the  and  parametric space of considered NP scenarios. By implementing the collider bounds on NP Wilson coefficients (WCs), we find that the parametric space of some NP WCs is significantly restrained. To see the clear influence of NP on the amplitude of the angular observables, we also calculate their numerical values in different  bins and show them through bar plots. We hope that their precise measurements will help to discriminate various NP scenarios.

Probing New Physics in Light of Recent Developments in → Transitions

The symmetries arise due to heavy quarks, and the large energy limit helps us to reduce the number of independent form factors in the heavy-to-light <math><mi>B</mi></math>-meson decays. It is expected that these symmetry relations are not exact and that they are broken by the perturbative effects, namely, the vertex corrections and the hard-spectator scatterings. The former are included in the form factors via vertex renormalization, whereas the latter are calculated through light-cone distribution amplitudes. We first calculate these symmetry breaking corrections to the form factors involved in semileptonic <math><mi>B</mi></math>-meson to an axial-vector (<math><mrow><msub><mrow><mi>K</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow></math>)-meson decay. Later, by using these form factors we see their effect on the physical observables such as the zero position of the forward-backward <math><mo>(</mo><msub><mi>A</mi><mrow><mi>F</mi><mi>B</mi></mrow></msub><mo>)</mo></math> asymmetry and the longitudinal lepton polarization (<math><msub><mi>P</mi><mi>L</mi></msub></math>) asymmetry in <math><mi>B</mi><mo>→</mo><msub><mi>K</mi><mn>1</mn></msub><mo>(</mo><mn>1270</mn><mo>)</mo><msup><mi>μ</mi><mo>+</mo></msup><msup><mi>μ</mi><mo>−</mo></msup></math> decay. We find that as a result of these corrections to the form factors, the zero position of the forward-backward asymmetry is shifted by 10% from its SM value, while the effects on <math><msub><mi>P</mi><mi>L</mi></msub></math> are rather insignificant.

Arslan Sikandar

Canada

M. Jamil Aslam

Vertex renormalization and hard scattering symmetry breaking corrections to <math><mi>B</mi></math> to axial vector meson form factors at large recoil

In 2015, the LHCb collaboration measured the differential branching ratio , the lepton- and hadron-side forward–backward asymmetries, denoted by and , respectively, in the range GeV with 3 fb of data. Motivated by these measurements, we perform an analysis of -dependent angular observables at large- and low- recoil in the standard model (SM) and in a family non-universal model. The exclusive transition is governed by the form factors, and in the present study we use the recently performed high-precision lattice QCD calculations that have well-controlled uncertainties, especially in the GeV bin. Using the full four-folded angular distribution of decay, first of all we focus on calculations of the experimentally measured , , and in the SM and compare their numerical values with the measurements in appropriate bins of . In case of a possible discrepancy between the SM prediction and the measurements, we try to see if these can be accommodated though the extra neutral boson. We find that in the dimuon momentum range GeV the value of and central value of in the model is compatible with the measured values. In addition, the fraction of longitudinal polarization of the dimuon was measured to be in GeV at the LHCb. We find that in this bin the value found in the model is close to the observed values. After comparing the results of these observables, we have proposed other observables such as and with and coefficients of different foldings in different bins of in the SM and model. We illustrate that the experimental observations of the -dependent angular observables calculated here in several bins of can help to test the predictions of the SM and unravel new physics contributions arising due to the model in decays.

Aqsa Nasrullah

China

M Jamil Aslam

Analysis of angular observables of decay in the standard and models