Related papers: Relevant results from the NA48 experiment
NA62, an experiment at the CERN SPS to measure the branching ratio for the decay K+ -> pi+ nu nu-bar with ~10% precision, will observe ~10^13 K+ decays in its fiducial volume, and will thus also be able to carry out a rich program to search…
The NA48/2 experiment at CERN reports the first observation of the $K^{\pm} \rightarrow \pi^{0} \pi^{0} \mu^{\pm} \nu$ decay based on a sample of 2437 candidates with 15% background contamination collected in 2003--2004. The decay branching…
A sample of $1.69\times 10^7$ fully reconstructed $\pi^0\to\gamma e^+e^-$ decay candidates collected by the NA48/2 experiment at CERN in 2003--2004 is analysed to search for the dark photon ($A'$) production in the $\pi^0\to\gamma A'$ decay…
The $K^+\rightarrow \pi^+ \nu \bar \nu$ decay is theoretically one of the cleanest meson decays and so a good place to look for indirect effects of new physics complementary to LHC searches. The NA62 experiment at CERN is designed to…
The present status of CP violation in decays of neutral kaons is reviewed. In addition selected rare decays of both K and B mesons are discussed. The emphasis is in particular on observables that can be reliably calculated and thus offer…
The ratio $\epsilon'/\epsilon$ measures the size of the direct CP violation in $K_L\to\pi\pi$ decays $(\epsilon^\prime)$ relative to the indirect one described by $\epsilon$ and is very sensitive to new sources of CP violation. As such it…
The results of a search for $\pi^0$ decays to a photon and an invisible massive dark photon at the NA62 experiment at the CERN SPS are reported. From a total of $4.12\times10^8$ tagged $\pi^0$ mesons, no signal is observed. Assuming a…
Searches for lepton number violating $K^+\to\pi^-e^+e^+$ and $K^+\to\pi^-\pi^0e^+e^+$ decays have been performed using the complete dataset collected by the NA62 experiment at CERN in 2016-2018. Upper limits of $5.3\times 10^{-11}$ and…
We report an improved measurement of direct CP violation in the decay B0 --> K+pi-, and a search for CP violation in the decays B+ --> K+pi0 and B+ --> pi+pi0. The measured CP violating asymmetries are…
The NA61/SHINE fixed-target experiment at the CERN SPS studies the onset of deconfinement and searches for the critical point of strongly interacting matter by measuring hadron production as a function of the collision energy and the…
After $CP$ violation was discovered in the $K_L \to \pi^+\pi^-$ decay, many theories were proposed to explain it, and the Kobayashi-Maskawa model and the Superweak model lasted for many years as strong candidates. High-precision kaon…
Recent results from the NA48/2 experiment are presented. The $\pi\pi$ scattering lengths $a_0^0$ and $a_0^2$ have been extracted from the cusp in the $M_{00}^2$ distribution of $K^\pm \to \pi^\pm \pi^0 \pi^0$ decays and from the $K^\pm \to…
New measurements of the $\eta$ and $K^0$ masses have been performed using decays to 3$\pi^0$ with the NA48 detector at the CERN SPS. Using symmetric decays to reduce systematic effects, the results $M(\eta) = 547.843\pm0.051$ MeV/c$^2$ and…
The highlights and conflicts at the B Factories are briefly reviewed. $CP$ violation was established in 2001 in $B^0 \to J/\psi K_S$ and related modes, which has now become a precision measurement of CP violation in $B^0$-$\bar B^0$ mixing.…
$CP$ violation experiments, new measurements of the parameters of the neutral \K\ system and searches for rare decays are summarized. Perspectives for the near future are presented.
The NA62 experiment at CERN aims to make a precision measurement of the ultra-rare decay $K^{+} \rightarrow \pi^{+}\nu\overline{\nu}$, and relies on a differential Cherenkov detector (KTAG) to identify charged kaons at an average rate of 50…
The NA62 experiment is a fixed-target experiment at CERN SPS. The main goal of the experiment is to measure the branching ratio of the ultra-rare kaon decay $K^{+}\to\pi^{+}\nu\bar\nu$. The NA62 detector allows also to study other rare kaon…
Rare kaon decays are an important testing ground of the electroweak flavor theory: They can provide new signals of CP-violating phenomena. The interplay of long-distance QCD effects in strangeness-changing transitions can be analyzed with…
The NA61/SHINE experiment is a fixed-target, broad acceptance facility at the CERN SPS. This contribution summarizes the most recent results from the strong interactions NA61/SHINE programme and presents news on the detector upgrade in…
The study of $CP$ violation in hyperon transitions has a long history. In the early 2000s the HyperCP experiment made a major effort to seek $CP$-odd signals in the decay sequence $\Xi^-\to\Lambda \pi^-$ and $\Lambda\to p\pi^-$, which…