We show that the QCD factorization approach for B-meson decays to charmless hadronic two-body final states can be extended to include electromagnetic corrections. The presence of electrically charged final-state particles complicates the framework. Nevertheless, the factorization formula takes the same form as in QCD alone, with appropriate generalizations of the definitions of light-cone distribution amplitudes and form factors to include QED effects. More precisely, we factorize QED effects above the strong interaction scale ΛQCD for the non-radiative matrix elements $$ \left\langle {M}_1{M}_2\left|{Q}_i\right|\overline{B}\right\rangle $$ M 1 M 2 Q i B ¯ of the current-current operators from the effective weak interactions. The rates of the branching fractions for the infrared-finite observables $$ \overline{B}\to {M}_1{M}_2\left(\gamma \right) $$ B ¯ → M 1 M 2 γ with photons of maximal energy ∆E ≪ ΛQCD is then obtained by multiplying with the soft-photon exponentiation factors. We provide first estimates for the various electromagnetic corrections, and in particular quantify their impact on the πK ratios and sum rules that are often used as diagnostics of New Physics.

Conventional, hadronic matter consists of baryons and mesons made of three quarks and a quark–antiquark pair, respectively1,2. Here, we report the observation of a hadronic state containing four quarks in the Large Hadron Collider beauty experiment. This so-called tetraquark contains two charm quarks, a $$\overline{{{{{u}}}}}$$ u ¯ and a $$\overline{{{{{d}}}}}$$ d ¯ quark. This exotic state has a mass of approximately 3,875 MeV and manifests as a narrow peak in the mass spectrum of D0D0π+ mesons just below the D*+D0 mass threshold. The near-threshold mass together with the narrow width reveals the resonance nature of the state.

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We present the first determination of Vcb from inclusive $$ B\to {X}_c \ell {\overline{v}}_{\ell} $$ B → X c ℓ v ¯ ℓ using moments of the dilepton invariant mass, q2. These moments are reparametrization invariant quantities and depend on a reduced set of non-perturbative parameters. This reduced set of parameters opens a new path to extract these parameters up to $$ 1/{m}_b^4 $$ 1 / m b 4 purely from data and can potentially reduce the uncertainty on Vcb. In this paper, we present our first determination of Vcb using this method. Combining the recent measurements of q2 moments by Belle and Belle II, our default fit gives |Vcb| = (41.69±0.63)·10−3. This result presents an important independent cross check of, and is consistent with, the previous state-of-the-art inclusive determinations using lepton energy and hadronic invariant mass moments.

We study the phenomenology of electric dipole moments (EDMs) induced in various scalar leptoquark models. We consider generic leptoquark couplings to quarks and leptons and match to Standard Model effective field theory. After evolving the resulting operators to low energies, we connect to EDM experiments by using up-to-date hadronic, nuclear, and atomic matrix elements. We show that current experimental limits set strong constraints on the possible CP-violating phases in leptoquark models. Depending on the quarks and leptons involved in the interaction, the existing searches for EDMs of leptons, nucleons, atoms, and molecules all play a role in constraining the CP-violating couplings. We discuss the impact of hadronic and nuclear uncertainties as well as the sensitivities that can be achieved with future EDM experiments. Finally, we study the impact of EDM constraints on a specific leptoquark model that can explain the recent B-physics anomalies. arXiv:1809.09114v2 [hep-ph]

The determination of V cb relies on the Heavy-Quark Expansion and the extraction of the non-perturbative matrix elements from inclusive b → c decays. The proliferation of these matrix elements complicates their extraction at 1/m 4 b and higher, thereby limiting the V cb extraction. Reparametrization invariance links different operators in the Heavy-Quark expansion thus reducing the number of independent operators at 1/m 4 b to eight for the total rate. We show that this reduction also holds for spectral moments as long as they are defined by reparametrization invariant weight-functions. This is valid in particular for the leptonic invariant mass spectrum (q 2 ), i.e. the differential rate and its moments. Currently, V cb is determined by fitting the energy and hadronic mass moments, which do not manifest this parameter reduction and depend on the full set of 13 matrix elements up to 1/m 4 b . In light of this, we propose an experimental analysis of the q 2 moments to open the possibility of a model-independent V cb extraction from semileptonic decays including the 1/m 4 b terms in a fully data-driven way.

We test a data-driven approach based on QCD factorization for charmless three-body B-decays by confronting it to measurements of CP violation in B − → π − π + π − . While some of the needed non-perturbative objects can be directly extracted from data, some others can, so far, only be modelled. Although this approach is currently model dependent, we comment on the perspectives to reduce this model dependence. While our model naturally accommodates the gross features of the Dalitz distribution, it cannot quantitatively explain the details seen in the current experimental data on local CP asymmetries. We comment on possible refinements of our simple model and conclude by briefly discussing a possible extension of the model to large invariant masses, where large local CP asymmetries have been measured.

The system offers a powerful laboratory to probe strong and weak interactions. Using the isospin symmetry, we determine hadronic parameters from data where new measurements of direct CP violation in resolve a discrete ambiguity. With the help of the SU (3) flavour symmetry, the parameters can be converted into their counterparts, thereby allowing us to make predictions of observables. A particularly interesting decay is as it exhibits mixing-induced CP violation. Using an isospin relation, complemented with a robust SU (3) input, we calculate correlations between the direct and mixing-induced CP asymmetries of , which are the theoretically cleanest probes. Interestingly, they show tensions with respect to the Standard Model. Should this puzzle originate from New Physics, electroweak penguins offer an attractive scenario for new particles to enter. We present a strategy to determine the parameters characterising these topologies and obtain the state-of-the-art picture from current data. In the future, this method will allow us to reveal the dynamics and to obtain insights into the electroweak penguin sector with unprecedented precision.