In this talk, I will discuss the current status and prospects in inclusive semileptonic beauty and charm decays from the theoretical side. I will introduce the open-source package Kolya, developed to predict inclusive beauty semileptonic rates within the SM and beyond. I will discuss the status of the Vcb determinations from semileptonic inclusive B decays using all available data. I will...
The Heavy Quark Expansion (HQE) has become the major tool to perform precision calculations for inclusive heavy hadron decays. With this method, $V_{cb}$ has been extracted with percent-level precision from moments of $B\to X_c\ell\bar{\nu}$. The HQE is an expansion in $1/m_b$ and introduces nonperturbative HQE matrix elements which can be extracted from data.
To further increase the...
The present LHCb anomalies in the post-$R_K^*$ era are obscured by still unknown power corrections to these exclusive modes. The method of refactorization is an option to solve this problem in the long run. We present a successful example of the these new techniques in SCET within the power corrections to the inclusive $\bar B \to X_s \gamma$ decay. Another option is the crosscheck with...
The inclusive radiative decay mode $B \to X_s \gamma$ provides an important channel for new physics searches.
When the photon energy is large, $m_b - 2 E_\gamma \sim \mathcal{O}(\Lambda_{\rm QCD})$, methods from soft-collinear EFT can be used to construct a systematic heavy-quark expansion.
In this talk, I will discuss how to include $\mathcal{O}(\alpha_s)$ corrections to the...
The LHCb experiment has produced many intriguing results presenting tensions with respect to the Standard Model. These anomalies point towards potential contributions from New Physics. In particular, the anomalies observed in the decay $B^0 \rightarrow K^{*0} \mu^+ \mu^-$ motivate unbinned analyses in dimuon invariant mass squared ($q^2$), where more information about the decay can be...
ATLAS B-physics analysis exploit low and medium momenta leptons and hadrons, combined in trigger signatures, adapting with levels of instantaneous luminosity during LHC spills. The dedicated trigger strategies over Run2 and Run3 lead to collect data allowing high precision tests of HF phenomena, covering: rare decays, high precision measurements in CKM favoured B-hadron decays and HF...
Motivated by the remarkable Belle II experimental result on $B\to K ^{}\, E_{\rm miss}$, and phenomenological difficulties in accommodating it exclusively in terms of processes with SM neutrino final states, we systematically investigate possibilities that $E_{\rm miss}$ comes not only from the SM neutrinos but also from other light undetected particles. We consider both single scalar or...
In modern experiments on flavour physics it is possible to search for the decays of $B$’s, $D$’s, or $\tau$’s into final states with heavy neutrinos $N$ (a.k.a. heavy neutral leptons). I present a common study of theorists and experimentalists from Belle II on constraints on $B \rightarrow D^{*} \ell N$. Next I discuss the status of the theory predictions of the various $N$ decay rates. In...
Exclusive $B$-decays provide valuable insights into physics beyond the Standard Model and measurements of Standard Model parameters. At large hadronic recoil Soft-Collinear Effective Theory is the appropriate theory to describe the QCD dynamics of heavy-to-light transitions and to resum logarithmic corrections to all orders in perturbation theory. However, since the relevant hadronic matrix...
Semileptonic $B_{(s)}$ decays are of great phenomenological interest and allow to extract the CKM matrix elements or test lepton flavor universality.
We explore $B_{(s)}$ decays with vector final states by studying $B_s\to D_s^*$ using the narrow width approximation. Taking advantage of existing data we present first results for the form factors using our setup based on RBC-UKQCD's 2+1 flavor...
We consider the combined measurements of CP-averaged decay rates and direct CP asymmetries of B±→K±ℓ+ℓ− and B±→π±ℓ+ℓ− to probe (non-local) four-quark operator matrix element contributions to rare semileptonic B meson decays. We also explore how their effects could be in principle disentangled from possible local new physics effects. We construct a ratio of CP-odd decay rate differences which...
We reinvestigate contributions of scalar leptoquarks in
anomalies and in
decays. Then, we update the constraints on parameter space and find which scalar leptoquarks remain viable and consistent with low-energy and high-energy flavour physics constraints. We comment on the implications of such selection.
Our ability to trace new physics in the $c\to u\ell^+\ell^-$ transitions
by measuring the $D\to\pi\ell^+\ell^-$ decay width
critically depends on the accurate knowledge of this decay amplitude,
dominated by an overlap of a singly Cabibbo suppressed weak decay and
electromagnetic lepton pair emission.
We calculate this amplitude, combining LCSRs with
hadronic dispersion relation, and...
Neutral charm meson mixing has first been observed in 2007 by Belle and Babar and soon after confirmed by LHCb and CDF. A longstanding discrepancy, of multiple orders of magnitude, is present between the leading order theoretical calculation of the so-called box diagram and the world average experimental value. The leading order theoretical value is extremely small due to the GIM mechanism...
The available data on exclusive $c\to s \ell \nu$ decays is analysed for three main purposes. First, a study of the relevant hadronic matrix elements is performed using dispersive bounds, resulting in theoretical predictions of observables which can be confronted with experimental results. Then, a combined Bayesian analysis of the experimental data is done for the extraction of the CKM element...
The study of charm-quark-related phenomena is a cornerstone of the flavour physics programme, as it offers unique opportunities to test the Standard Model and to explore different new physics scenarios. The observation of the CP asymmetries in the decays of neutral charm mesons to two light pseudoscalars by LHCb imposes up to date a question without a definite answer. In previous work we...
The calculation of local form factors involved in the SM predictions of semileptonic $B$-meson decays at low-$q^2$ is a crucial ingredient in the assessment of the $B$-anomalies.
We revisit their calculation in QCD Light-Cone Sum Rule with $B$-meson Light-Cone Distribution Amplitudes. In our strategy, we bypass the quark-hadron duality (QHD) approximation which usually contributes an unknown...
In this talk I will summarize the theory and phenomenology status of the inclusive penguin decay $B \to X_s \ell \ell$. In the high-$q^2$ (soft recoil) region above the narrow charmonium resonances, the inclusive rate is dominated by two exclusive modes $B \to K^{(*)}\ell \ell$. I will explain that this property of the spectrum provides an opportunity to apply the toolkit of inclusive B decays...
Over the last few years, a puzzling discrepancy in the non-leptonic $B$ to $D$ plus light meson decays has arisen, with large tensions between experimental measurements and theory prediction from QCD factorisation.
In this talk, I will summarise the current state of these discrepancies, discuss EFT models that would reduce the discrepancies, and then show how recent LHC measurements of top...
We study the penguin-mediated $\bar{B}_{d(s)}\to K^{(*)0}\bar{K}^{(*)0}$ and $\bar{B}_{d(s)}\to\bar{K}^{*0}(K^{*0})\phi$ transitions. We propose optimised observables $L_{K^(*)\bar{K}^(*)}$, $L_{K^*\phi}$ from the ratio of longitudinal branching ratios of these decays, with limited hadronic uncertainties and enhanced sensitivity to New Physics. $L_{K^{(*)}\bar{K}^{(*)}}$ deviates at the...
Exploiting the relation between real-space Wilsonian renormalization group transformations and gradient flow, we show how to determine the $\beta$ function and obtain the QCD $\Lambda$ parameter. Moreover, we use this framework to develop a novel nonperturbative renormalization scheme for local operators. We demonstrate our method using nonperturbative results based on simulations with...
Neutral meson mixing and meson lifetimes are theory-side parametrised in terms four-quark operators which can be determined by calculating weak decay matrix elements using lattice QCD.
While calculations of meson mixing matrix elements are standard, determinations of lifetimes typically suffer from complications in renormalisation procedures because dimension-6 four-quark operators can mix...
