Related papers: New insights concerning dimension-eight effects in…
I describe recent work with V. Cirigliano and E. Golowich on the effect of dimension eight operators on weak nonleptonic amplitudes. The basic message is that there is an inconsistency in the way that many calculations are traditionally…
We expose a potential flaw in standard treatments of weak decay amplitudes, including that of epsilon'/epsilon. We show that (contrary to conventional wisdom) dimension-eight operators do contribute to weak amplitudes, at order G_F alpha_s…
We discuss recent work which identifies a potential flaw in standard treatments of weak decay amplitudes, including that of epsilon'/epsilon. The point is that (contrary to conventional wisdom) dimension-eight operators contribute to weak…
The shift in focus towards searches for physics beyond the Standard Model (SM) employing model-independent Effective Field Theory (EFT) methods necessitates a rigorous approach to matching to guarantee the validity of the obtained results…
We compare recent theoretical determinations of weak matrix elements of the electroweak penguin operators Q7 and Q8. We pay special attention to the renormalization scheme dependence of these determinations as well as to the influence of…
A brief review of recent results on computing contributions of higher dimension operators to weak effective $\Delta S=1,2$ hamiltonians for light quarks is presented.
Besides their appearance at short distances \gtrsim 1/M_W, local dimension-eight operators also contribute to kaon matrix elements at long distances of order \gtrsim 1/mu_ope, where mu_ope is the scale controlling the Operator Product…
While all models of Majorana neutrino masses lead to the same dimension five effective operator, which does not conserve lepton number, the dimension six operators induced at low energies conserve lepton number and differ depending on the…
I briefly review some recent progress in the theory of nonleptonic B decays. After introducing the operator product expansion and the relevant effective Hamiltonian, I discuss the domain of validity and the theoretical justification of the…
We study dimension-eight effects in the Standard Model Effective Field Theory extended by right-handed neutrinos ($\nu$SMEFT). Using the Hilbert series formalism, we derive the complete basis of dimension-eight operators and confirm…
This review contains an overview of strong interaction effects in weak decays starting with a historical introduction. It contains a short overview of semileptonic decays and their relevance for measuring CKM matrix elements. The main part…
These lectures describe in detail the effective Hamiltonians for weak decays of mesons constructed by means of the operator product expansion and the renormalization group method. We calculate Wilson coeffcients of local operators, discuss…
Precision measurements of top-quark decays provide powerful probes of physics beyond the Standard Model (SM). While the impact of dimension-6 operators in the SM Effective Field Theory (SMEFT) has been extensively studied, the role of…
We discuss the structure of the mixing among dimension-eight operators in the SMEFT relying on the positivity of two-to-two forward scattering amplitudes. We uncover tens of new non-trivial zeros as well as hundreds of terms with definite…
Although the weak nonleptonic amplitudes of the Standard Model are notoriously difficult to calculate, we have produced a modified weak matrix element which can be analyzed using reliable methods. This hypothetical nonleptonic matrix…
We perform a complete study of the electroweak precision observables and electroweak gauge boson pair production in terms of the SMEFT up to ${\cal O}(1/\Lambda^4)$ under the assumption of universal, C and P conserving new physics. We show…
A non-technical description of the Operator Product Expansion and Renormalization Group techniques as applied to weak decays of mesons is presented. We use this opportunity to summarize briefly the present status of the next-to-leading QCD…
The precise measurement of the width difference \Delta\Gamma_s among the mass eigenstates of the B_s-\bar{B}_s system requires the calculation of the corresponding decay matrix to order \alpha_s/m_b. QCD corrections to power-suppressed…
The renormalization of the most general dimension-six four-fermion operators without power subtractions is studied at one loop in lattice perturbation theory using overlap fermions. As expected, operators with different chirality do not mix…
The calculation of higher twist (or dimension) corrections to physical quantities using operator product expansions is delicate. If dimensional regularization is used to regulate the ultra-violet divergences then there are ambiguities in…