相关论文: K_{l3} and pi_{e3} decays: radiative corrections a…
We present a detailed numerical study of the K_{e3} decays to O(p^6,(m_d-m_u)p^2,e^2p^2) in chiral perturbation theory with virtual photons and leptons. We describe the extraction of the CKM matrix element |V_{us}| from the experimental…
We present a complete calculation of the K_{l3} decays K^+ --> pi^0 l^+ nu_l and K^0 --> pi^- l^+ nu_l to O(p^4, (m_d-m_u) p^2, e^2 p^2) in chiral perturbation theory with virtual photons and leptons. We introduce the concept of generalized…
We study the radiative corrections to all Kl3 decay modes to leading non-trivial order in the chiral effective field theory, working with a fully inclusive prescription on real photon emission. We present new results for Kmu3 modes and…
Pionic beta decay \pi^+ to \pi^0 e^+ \nu_e is analyzed in chiral perturbation theory with virtual photons and leptons. All electromagnetic corrections up to order e^2 p^2 are taken into account. Theoretical results are confronted with…
We consider the lowest order radiative corrections for the decay $K^{\pm}\to \pi^0 e^{\pm} \nu$, usually referred as $K_{e3}^{\pm}$ decay. This decay is the best way to extract the value of the $V_{us}$ element of the CKM matrix. The…
The radiative corrections to the $\tau^-\to (P_1P_2)^-\nu_\tau$ ($P_{1,2}=\pi, K$) decays are calculated for the first time including the structure-dependent real photon corrections, which are obtained using Resonance Chiral Theory. Our…
We report a high-precision calculation of the Standard Model electroweak radiative corrections in the $K\to \pi e^+\nu(\gamma)$ decay as a part of the combined theory effort to understand the existing anomaly in the determinations of…
Motivated by recent experimental results and ongoing measurements, we review the chiral perturbation theory prediction for radiative Ke3 decays (neutral kaons). Special emphasis is given on the stability of the inner…
We evaluate the matrix elements for the radiative kaon decays $K^+ \to l^+\nu_l\gamma$, $l^+ \nu_l l'^+ l'^-$ and $K \to \pi l \nu_l\gamma$ \ ($l,\ l' = e,\mu$) to next-to-leading order in chiral perturbation theory. We calculate total…
We re-investigate the radiative charged kaon decay K+- --> pi0 e+- nu_e gamma in chiral perturbation theory, merging the chiral expansion with Low's theorem. We thoroughly analyze the precision of the predicted branching ratio relative to…
The measurements of $V_{us}$ in leptonic $(K_{\mu 2})$ and semileptonic $(K_{l3})$ kaon decays exhibit a $3\sigma$ disagreement, which could originate either from physics beyond the Standard Model or some large unidentified Standard Model…
The estimation of rare K decay matrix-elements from Kl3 experimental data is extended beyond LO in Chiral Perturbation Theory. Isospin-breaking effects at NLO (and partially NNLO) in the ChPT expansion, as well as QED radiative corrections…
We present a brief overview of the recent theoretical progress to describe the K_{l2} and K_{l3} decays. We discuss the interesting probes of the Standard Model offered by these decays such as the extraction of |V_{us}| and the test of the…
After a short status report on chiral perturbation theory, I review recent progress in determining some of the low-energy couplings by matching the effective theory to QCD. Consequences for K_{l3} decays and for the extraction of the CKM…
We propose a new theory framework to study the electroweak radiative corrections in $K_{l3}$ decays by combining the classic current algebra approach with the modern effective field theory. Under this framework, the most important…
We investigate radiative corrections to K --> 3 pi decays. In particular, we extend the non-relativistic framework developed recently to include real and virtual photons and show that, in a well-defined power counting scheme, the results…
We analyze the prospective impact of supersymmetric radiative corrections on tests of charged current universality involving light quarks and leptons. Working within the R-parity conserving Minimal Supersymmetric Standard Model, we compute…
Measured ratios of decay rates for Ke3/K2\pi, K\mu3/K2\pi and K\mu3/Ke3 are presented. These measurements are based on K^+- decays collected in a dedicated run in 2003 by the NA48/2 experiment at CERN. The results obtained are Ke3/K2\pi =…
Using a technique that is not subject to first-order SU(3) symmetry breaking effects, we determine the $V_{us}$ element of the CKM matrix from data on semileptonic hyperon decays. We obtain $V_{us}$ =0.2250(27). This value is of similar…
The rare decay K_L -> pi pi e e that has recently been observed by KTeV is analyzed in chiral perturbation theory at the one-loop level.