The past two decades have seen a remarkable advance in our understanding in our understanding of quark transitions, and in particular the production and decay of heavy flavour hadrons. In this talk I will review the present status of heavy flavour measurements constraining the CKM matrix which governs quark transitions in the Standard Model, as well as measurements probing rare and forbidden...
Several observables in B-meson decays show discrepancies between
experimental data and Standard Model (SM) predictions. Recently, LHCb
has updated their measurement of the lepton flavor universality (LFU)
observable RK and, finding a 3.1 σ deviation from the SM, reports
evidence for violation of LFU. This talk will give an overview of the
anomalies in rare B decays and...
Form factors describing exclusive semileptonic $B_{(s)}$ decays allow e.g. to extract the CKM matrix elements $|V_{ub}|$ and $|V_{cb}|$ or obtain predictions for R-ratios testing lepton flavor universality. Using the framework of lattice quantum chromodynamics, we present our results for the semileptonic $B_s \to D_s \ell \nu$, $B_s \to K \ell \nu$, and $B \to \pi \ell \nu$ decays.
First...
We revisit light-cone sum rule predictions for the full set of local B → π form factors, with focus on the systematic uncertainties that affect this method and carry out a combined fit with the precise lattice QCD results for all form factors simultaneously, in order to provide the most up-to-date exclusive determination of |Vub|. From the world average of the semileptonic B0 → π l ν decay we...
The determination of the CKM element Vcb from inclusive semileptonic
b → c semileptonic decays has reached a high precision thanks to a combination of theoretical and experimental efforts. Moreover, the long standing Vcb puzzle, a discrepancy between inclusive and exclusive determinations seems to be disappearing. In this talk, I will discuss the story of Vcb and how to continue towards even...
Recent high precision determinations of $V_{us}$ and $V_{ud}$ indicate towards anomalies in the first row of the CKM matrix. Namely, determination of $V_{ud}$ from beta decays and of $V_{us}$ from kaon decays imply a violation of first row unitarity at about $3\sigma$ level. Moreover, there is tension between determinations of $V_{us}$ obtained from leptonic $K\mu2$ and semileptonic $K\ell3$...
In this talk I will review how the anomalous magnetic moment of the muon and the B anomalies can be addressed by a combined explaination, by means of loop models characterized by minimal field content. Moreover, I will show how some of these model can also provide a viable DM candidate, accounting for the measured relic density while evading direct and indirect DM constraints.
Evidence for electron-muon universality violation that has been revealed in b→sℓℓ transitions in the observables $R_{K,K^\ast}$ by the LHCb Collaboration can be explained with spin-1 leptoquarks in $SU(2)_L$ singlet $V_1$ or triplet $V_3$ representations in the $\mathcal{O}(1−10)$ TeV range. We explore the sensitivity of the high luminosity LHC (HL-LHC) and future proton-proton colliders to...
In this talk I will present the updated Standard Model prediction of
the golden rare Kaon decay modes and the CP violating parameter
epsilon_K. I will focus on the recent theoretical improvements which
result in an increased sensitivity to physics beyond the Standard
Model. I will also present a computer program that provides the
results of the relevant perturbative calculations in a wide...
After reviewing combined solutions of flavor anomalies with the singlet and triplet scalar leptoquarks $S_1$ and $S_3$, I will present possible connections to Kaon physics observables. By assuming a flavor structure for the leptoquark couplings dictated by a minimally broken $U(2)^5$, we find that bound on $Br(K^+ \to \pi^+ \nu\nu)$ from NA62 puts already some tension in the model, while the...
Charged Lepton Flavor Violation (LFV) is a very clean probe of New Physics since it is forbidden in the Standard Model (SM). The observation of neutrino oscillation implies nonzero LFV rates, which however are highly suppressed by the smallness of neutrino masses. This makes LFV an appealing target of experimental searches, as its observation would unambiguously point to New Physics.
In...
We discuss the single LQ solutions to the problem of accommodating the observed hints of LFUV in B-decays. We then focus on the combination of two scalar leptoquarks R2 and S3 and formulate the model which can describe all of the anomalies. We update the previous results with a particular emphasis on the bounds arising from the high-pT tail of pp --> tau nu. We then consider several new...
I will review our recent work on lepton flavor non-universal and anomaly-free U(1) gauge extensions of the SM. The phenomenological discussion will be centered around flavor anomalies in rare B-meson decays and muon g-2. This talk is based on 2103.13991 (AG, Stangl, and Thomsen) and 2107.07518 (AG, Soreq, Stangl, Thomsen, and Zupan).
