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11 papers found.
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\( {R}_{D^{\left(*\right)}},{R}_{K^{\left(*\right)}} \) and neutrino mass in the 2HDM-III with right-handed neutrinos

Abstract Given that the two-Higgs-doublet model of type III (2HDM-III) has the potential to address the \( {R}_{D^{\left(*\right)}} \) anomalies while the resolution to the \( {R}_{K^{\left(*\right)}} \) deficits requires new degrees of freedom within this framework, we consider in this paper a unified scenario where the low-scale type-I seesaw mechanism is embedded into the 2HDM...

Mixing in the Minimal Flavor-Violating Two-Higgs-Doublet Models

The two-Higgs-doublet model (2HDM), as one of the simplest extensions of the Standard Model (SM), is obtained by adding another scalar doublet to the SM and is featured by a pair of charged Higgs, which could affect many low-energy processes. In the “Higgs basis“ for a generic 2HDM, only one scalar doublet gets a nonzero vacuum expectation value and, under the criterion of...

Study of the weak annihilation contributions in charmless \(\varvec{B_s\rightarrow VV}\) decays

In this paper, in order to probe the spectator-scattering and weak annihilation contributions in charmless \(B_s\rightarrow VV\) (where V stands for a light vector meson) decays, we perform the \(\chi ^2\)-analyses for the endpoint parameters within the QCD factorization framework, under the constraints from the measured \(\bar{B}_{s}\rightarrow \) \(\rho ^0\phi \), \(\phi K^{*0...

The \(\varvec{\Lambda _b\rightarrow \Lambda (\rightarrow p\pi ^-)\mu ^+\mu ^-}\) decay in the aligned two-Higgs-doublet model

The rare baryonic decay \(\Lambda _b\rightarrow \Lambda (\rightarrow p\pi ^-)\mu ^+\mu ^-\) provides valuable complementary information compared to the corresponding mesonic \(b\rightarrow s\mu ^+\mu ^-\) transition. In this paper, using the latest high-precision lattice QCD calculation of the \(\Lambda _b\rightarrow \Lambda \) transition form factors, we study this interesting...

\(\varvec{B^0\rightarrow K^{*0}\mu ^+\mu ^-}\) decay in the aligned two-Higgs-doublet model

In the aligned two-Higgs-doublet model, we perform a complete one-loop computation of the short-distance Wilson coefficients \(C_{7,9,10}^{(\prime )}\), which are the most relevant ones for \(b\rightarrow s\ell ^+\ell ^-\) transitions. It is found that, when the model parameter \(\left| \varsigma _{u}\right| \) is much smaller than \(\left| \varsigma _{d}\right| \), the charged...

\( {\varLambda}_b\to {\varLambda}_c\tau {\overline{\nu}}_{\tau } \) decay in scalar and vector leptoquark scenarios

It has been shown that the anomalies observed in \( \overline{B}\to {D}^{\left(\ast \right)}\tau {\overline{\nu}}_{\tau } \) and \( \overline{B}\to \overline{K}{\ell}^{+}{\ell}^{-} \) decays can be resolved by adding a single scalar or vector leptoquark to the Standard Model, while constraints from other precision measurements in the flavour sector can be satisfied without fine...

Two-body non-leptonic heavy-to-heavy decays at NNLO in QCD factorization

We evaluate in the framework of QCD factorization the two-loop vertex corrections to the decays \( {\overline{B}}_{(s)}\to {D}_{(s)}^{\left(\ast \right)+}{L}^{-} \) and Λ b  → Λ c + L −, where L is a light meson from the set {π, ρ, K (∗) , a 1}. These decays are paradigms of the QCD factorization approach since only the colour-allowed tree amplitude contributes at leading power...

Revisiting the one leptoquark solution to the R(D (∗)) anomalies and its phenomenological implications

It has been shown recently that the anomalies observed in \( \overline{B}\to {D}^{\left(*\right)}\tau {\overline{\nu}}_{\tau } \) and \( \overline{B}\to \overline{K}{\ell}^{+}{\ell}^{-} \) decays could be resolved with just one scalar leptoquark. Fitting to the current data on R(D(∗)) along with acceptable q 2 distributions in \( \overline{B}\to {D}^{\left(\ast \right)}\tau...

\({B_s^0}\) – \({\bar{B}}_s^0\) mixing within minimal flavor-violating two-Higgs-doublet models

In the “Higgs basis” for a generic 2HDM, only one scalar doublet gets a nonzero vacuum expectation value and, under the criterion of minimal flavor violation, the other one is fixed to be either color-singlet or color-octet, which are named as the type-III and type-C models, respectively. In this paper, the charged-Higgs effects of these two models on \(B_s^0\)–\({\bar{B}}_s^0...

Flavour-changing top decays in the aligned two-Higgs-doublet model

We perform a complete one-loop computation of the two-body flavour-changing top decays t → ch and t → cV (V = γ, Z), within the aligned two-Higgs-doublet model. We evaluate the impact of the model parameters on the associated branching ratios, taking into account constraints from flavour data and measurements of the Higgs properties. Assuming that the 125 GeV Higgs corresponds to...

\( B_{s,d}^0 \) → ℓ + ℓ − decays in the aligned two-Higgs-doublet model

Abstract The rare decays \( B_{s,d}^0 \) → ℓ + ℓ − are analyzed within the general framework of the aligned two-Higgs doublet model. We present a complete one-loop calculation of the relevant short-distance Wilson coefficients, giving a detailed technical summary of our results and comparing them with previous calculations performed in particular limits or approximations. We...