Related papers: KOTO vs. NA62 Dark Scalar Searches
The search for light and long-lived particles at the LHC will be intensified in the upcoming years with a prominent role of the new FASER experiment. In this study, we discuss how FASER could independently probe such scenarios relevant for…
The KOTO experiment is a particle physics experiment located in J-PARC, Japan, aiming to explore physics beyond the Standard Model by measuring the branching ratio of the $K_L\rightarrow\pi^{0}\nu\bar{\nu}$ decay. This decay has not yet…
Recently, the KOTO experiment reported their new preliminary result of searching for the decay $K_L\to\pi^0\nu\bar{\nu}$. Three candidate events were observed in the signal region, which exceed significantly the expectation based on the…
The KOTO II experiment is proposed to measure the branching ratio of the decay $K_L\to\pi^0\nu\bar{\nu}$ at J-PARC. With a beamline to extract long-lived neutral kaons at 5 degrees from a production target, the single event sensitivity of…
Rare kaon decays are excellent probes of light, new weakly-coupled particles. If such particles $X$ couple preferentially to muons, they can be produced in $K\to \mu \nu X$ decays. In this letter we evaluate the future sensitivity for this…
The Grossman-Nir bound concept is robust, but the common perception of $K_L \to \pi^0\nu\bar\nu < 1.4 \times 10^{-9}$ may be circumvented. Because of the blinding $K\pi2$(3) decay, $K^+$ decay experiments such as E787/E949 and the currently…
The experimental status of the $K \to \pi \nu \bar{\nu}$ search is presented. The $K \to \pi \nu \bar{\nu}$ decay is sensitive to New Physics because it is theoretically pristine and highly suppressed. The $K_L^0 \to \pi^0 \nu \bar{\nu}$…
While the main goal of the J-PARC KOTO experiment is to measure the rare decay $K_L \to \pi^0 \nu \bar \nu$, the unique setup of KOTO raises the possibility to search for physics beyond the Standard Model, in an attempt to probe parts of…
NA62 is a fixed target kaon experiment at the CERN SPS which aims at measuring the branching ratio of the $K^+\to\pi^+\nu\bar{\nu}$ decay with 10% precision. This ultra-rare kaon decay is theoretically extremely clean and an ideal place to…
Recently, the KOTO experiment at J-PARC has observed three anomalous events in the flavor-changing rare decay $K_L \to \pi^0 \nu \bar\nu$, which indicates that the corresponding branching ratio is almost two orders of magnitude larger than…
The rare decays $\mathrm{K}^+\to \pi^+ \nu \bar{\nu}$ and $\mathrm{K_L}\to \pi^0 \nu \bar{\nu}$ are extremely attractive processes to study flavor physics because they are both exceptionally clean from a theoretical point of view. These…
We argue that demanding a consistent cosmological history, including the absence of domain walls and strongly interacting relics at the Peccei-Quinn scale, singles out two concrete realizations of hadronic QCD axions as viable dark matter…
The KOTO experiment recently reported four candidate events in the signal region of $K_L\to \pi^0 \nu\bar\nu$ search, where the standard model only expects $0.10\pm 0.02$ events. If confirmed, this requires physics beyond the standard model…
The KOTO experiment at the J-PARC research facility in Tokai, Japan aims to observe and measure the rare decay of the neutral kaon, $K_L^0 \rightarrow \pi^0 \nu \bar{\nu}$. This decay has a Standard Model (SM) predicted branching ratio (BR)…
The $K\to\pi\nu\bar{\nu}$ ultra-rare decays are precisely computed in the Standard Model (SM) and are ideal probes for physics beyond the SM. The NA62 experiment at the CERN SPS is designed to measure the charged channel with a precision of…
Searches for lepton flavour violation and lepton number violation in kaon decays by the NA62 and NA48/2 experiments at CERN are presented. A new measurement of the ratio of charged kaon leptonic decay rates…
Dark sector models present a rich phenomenology that requires high-intensity beams and precision detectors for thorough exploration. The NA62 experiment has already published several constraints on dark sector models, leveraging proton beam…
The rare kaon decay $K_L\to\pi^0\nu\bar{\nu}$ is extremely sensitive to new physics, because the contribution to this decay in the Standard Model (SM) is highly suppressed and known very accurately; the branching ratio is $3\times 10^{-11}$…
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 KOTO ($K^0$ at Tokai) experiment aims to observe the CP-violating rare decay $K_L \rightarrow \pi^0 \nu \bar{\nu}$ by using a long-lived neutral-kaon beam produced by the 30 GeV proton beam at the Japan Proton Accelerator Research…