Related papers: Angular Distributions of B -> K ll Decays
The determination of the differential branching fraction and the first angular analysis of the decay $B_s^0\to\phi\mu^{+}\mu^{-}$ are presented using data, corresponding to an integrated luminosity of $1.0\,{\rm fb}^{-1}$, collected by the…
The LHCb experiment observed B+ --> pi+ mu+ mu- decay with 1.0 fb^-1 data, which is the first measurement of a flavor changing neutral current b --> d l+ l- decay (l = e, mu). Based on QCD factorization, we give Standard Model predictions…
There are some slight tensions with the SM predictions within the latest LHCb measurements. Besides the known anomaly in one angular observable of the rare decay B -> K* mu+ mu-, another small discrepancy recently occurred. The ratio R_K =…
The decay mode $B\to K^*\ell^+\ell^-$ results in the measurement of a large number of related observables by studying the angular distribution of the decay products and is regarded as a sensitive probe of physics beyond the standard model…
Besides being important to determine Standard Model parameters such as the CKM matrix elements $|V_{cb}|$ and $|V_{ub}|$, semileptonic $B$ decays seem also promising to reveal new physics (NP) phenomena, in particular in connection with the…
The Higgs-boson decay h -> gamma l+ l- for various lepton states l = (e, mu, tau) is analyzed. The differential decay width and forward-backward asymmetry are calculated as functions of the dilepton invariant mass in a model where the Higgs…
Angular distributions of the decay B$^+$ $\to$ K$^*$(892)$^+\mu^+\mu^-$ are studied using events collected with the CMS detector in $\sqrt{s} =$ 8 TeV proton-proton collisions at the LHC, corresponding to an integrated luminosity of 20.0…
The experimental information on b --> s l^+ l^- decays has grown enormously during the last couple of years due to BaBar, Belle, CDF and LHCb. Especially, exclusive modes B --> K^(*) l^+ l^-, which have the largest rate and are easily…
This paper describes the angular distribution of $\Lambda_b^0\to \Lambda(\to pK^-)\ell^+\ell^-$ decays. A full expression is given for the case of multiple interfering spin-states with spin $\leq \tfrac{5}{2}$. This distribution is relevant…
In anticipation of abundant $B^*$ data samples at high-luminosity heavy-flavor experiments in the future, the tree-dominated semileptonic $\bar{B}^*_{u,d,s} \to P \ell^- \bar{\nu}_\ell$ $(P=D\,,D_s\,,\pi\,,K)$ decays are studied within the…
A test of lepton universality between muons and electrons is performed using $B^+\to K^+\ell^+\ell^-$ decays (where $\ell$ = $e$, $\mu$), in the dilepton invariant-mass-squared region above 14.3 GeV$^2/c^4$. The data used for the…
We study the rare radiative dileptonic decays $B^0(B_s)\to \gamma\ell^+\ell^-$ ($\ell=e,\mu$) in the standard model. By using the $B$ meson wave function constrained by non-leptonic decays, the branching ratios turn out to be of the order…
We present new calculations of the differential decay rates for $H\to \ell^+\ell^- \gamma$ with $\ell=e$ or $\mu$ in the Standard Model. The branching fractions and forward-backward asymmetries, defined in terms of the flight direction of…
We present the angular distribution of the four-fold $B\to\rho (\to\pi\pi)\mu^{+}\mu^{-}$ and $B\to a_{1}(\to\rho_{\parallel, \perp}\pi)\mu^{+}\mu^{-}$ decays both in the Standard Model and the family non-universal $Z^{\prime}$ model. At…
We consider the axial-vector mesons $K_1(1270)$ and $K_1(1400)$ as a mixture of two $|^3P_1\rangle$ and $|^1P_1\rangle$ states with the mixing angle $\theta$ that equal to $(-34\pm 13)^\circ$. We calculate the light-front distribution…
Using the helicity amplitude technique, we derive differential decay widths and angular distributions for the decay cascade $D\to K_{1}(1270,1400)\ell^+\nu_{\ell}\to (K\pi\pi)\ell^+\nu_{\ell} (\ell=e,\mu)$, in which the electron and muon…
We study the $L\to l l' l' \nu_l \nu_L$ decays ($L=\tau,\mu$; $l,l'=\mu,e$) in the Standard Model (SM) and in the effective field theory (EFT) description of the weak charged current at low energy, both for polarized and unpolarized $L$,…
Among the various "rare" semi-leptonic decays of $B$-mesons the $B \to K^* \ell^+ \ell^-$ mode is of special interest. This is because it has the highest branching ratio among all the semi-leptonic B decays within the SM. This channel also…
We discuss the angular distribution analysis of $B\to J/\psi K^{*}$ decays and a way to resolve discrete ambiguites in the determination of the unitary triangle $\phi_1(=\beta)$. We study the status of factorization hypothesis in the…
We analyze $K_L$ lepton pair decays of $K_L \to l^+\l^-\gamma$ and $K_L \to l^+l^-l'^+l'^-$ $(l, l'=e, \mu)$ within the framework of the light-front QCD approach (LFQA). With the $K_L \to \gamma^* \gamma^*$ form factors evaluated in a model…