Related papers: Estimating epsilon'/epsilon. A Review
I first motivate why we may want to look at possible new physics contributions to epsilon' given relatively clear experimental but unclear theoretical situations. I reexamine the supersymmetric contribution to epsilon' and find an important…
We present for the first time a master formula for $\varepsilon'/\varepsilon$, the ratio probing direct CP violation in $K \to \pi\pi$ decays, valid in any theory beyond the Standard Model (BSM). The formula makes use of hadronic matrix…
We review the present status of CP violation in the standard model. Subsequently we make an excursion in the future in order to see what we could expect in this field in this and the next decade. We present various strategies for the…
Searches for experimental manifestations of CP violation have born much fruit in recent years with the discovery of direct CP violation and the first evidence of CP violation outside of the neutral kaon system. Nevertheless we still know…
Recent progress in the determination of hadronic matrix elements has revealed a tension between the measured value of $\epsilon_K^{\prime}/\epsilon_K$, which quantifies direct $CP$ violation in $K \to \pi\pi$ decays, and the Standard-Model…
I shortly review the present status of the theoretical calculations of eps'/eps and the comparison with the present experimental results. I discuss the role of higher order chiral corrections and in general of non-factorizable contributions…
We study four different models for CP violation: the standard (KM) model, the aspon model of spontaneous breaking and two models of soft breaking. In all except the standard model, the strong CP problem is addressed and solved. Testable…
I discuss the estimate of the CP-violating parameter eps'/eps based on hadronic matrix elements computed in the chiral quark model. This estimate suggested, before the current experimental results, that the favored value of eps'/eps in the…
In the standard model (SM), the CP violation is introduced through a single phase in the CKM matrix. The neutral kaon system is one of the most precise channels to test how the SM theory describes the experiment data such as $\epsilon_K$…
We investigate direct CP violation in neutral meson decays by reconstructing the associated density matrices and measuring their difference using the trace distance. Our results cover neutral kaon decays into two scalar triplets of isospin…
The known isospin-breaking contributions to the $K\rightarrow \pi\pi$ amplitudes are reanalyzed, taking into account our current understanding of the quark masses and the relevant non-perturbative inputs. We present a complete numerical…
We present precise measurements of CP and CPT symmetry based on the full dataset of K to 2pi decays collected by the KTeV experiment at FNAL. We measure the direct CP violation parameter Re(epsilon'/epsilon) = (19.2 pm 2.1)x10-4. We also…
We present precise measurements of CP and CPT symmetry based on the full dataset of K to 2pi decays collected by the KTeV experiment at FNAL. We measure the direct CP violation parameter Re(epsilon'/epsilon) = (19.2 pm 2.1)x10-4. We also…
I review the current theoretical estimates of the CP-violating parameter eps'/eps, compare them to the experimental result and suggest a few guidelines in using the theoretical results.
CP violation is an important tool to test the Standard Model and his extensions. We describe kaon physics observables testing CP violation and more in general short distance physics. Channels under consideration will be K -> pi nu nu, K ->…
The Standard Model prediction for epsilon'/epsilon is updated, taking into account the most recent theoretical developments. The final numerical value, epsilon'/\epsilon = (17\pm 6) x 10^{-4}, is in good agreement with present measurements.
I review CP violation in the standard model (SM). I also describe the predictions for CP violation in the B system, along with signals for physics beyond the SM. I stress the numerous contributions of Pat O'Donnell to this subject. Finally,…
We discuss a new estimate of $\varepsilon '/\varepsilon$ in the kaon system. The present approach is based on the evaluation of the hadronic matrix elements of the \mbox{$\Delta S =1$} effective quark lagrangian by means of the chiral quark…
We analyze the rare kaon decays $K_L \to \pi^0 \nu \bar \nu$, $K^+ \to \pi^+ \nu \bar \nu$, $K_L \to \pi^0 e^+ e^-$ and $K_L \to \mu^+ \mu^-$ in conjunction with the CP violating ratio $\epsilon'/\epsilon$ in a general class of…
The first lattice result from the RBC and UKQCD Collaborations and improved perturbative calculations of $\varepsilon^{\prime}_K / \varepsilon_K$ have implied that the Standard-Model (SM) expectation deviates from measured values at the…