Within the framework of a low-energy effective field theory we consider the procedure of extraction of the S-wave kaon–nucleon scattering lengths a0 and a1 from a combined fit to the kaonic hydrogen and kaonic deuterium data. It is demonstrated that, if the present DEAR central values for the kaonic hydrogen ground-state energy and width are used in the analysis of the data, a solution for a0 a...

The latest results from the NA48/2 collaboration on charged kaon decays will be reviewed in this paper. The high statistics available, collected during 2003 and 2004 runs, allows the study of charged kaon decays up to branching ratios (BR) of ∼ 10−8. The status of the analyses of several radiative decays (K± → π±π0γ, K± → π±γγ, K± → π±e+e−γ and K± → π±e+e−) will be discussed, including BR measu...

Kaon production cross sections in nucleon-nucleon, nucleon-delta and delta-delta interactions are studied in a boson exchange model. For the latter two interactions, the exchanged pion can be on-mass shell, only contributions due to a virtual pion are included via the Peierls method by taking into account the finite delta width. With these cross sections and also those for pion-baryon interacti...

This talk is an overview of Chiral Perturbation Theory for Kaon physics as far as not covered by other speakers. It includes a short introduction to the strengths and weaknesses of Chiral Perturbation Theory and its applications to semileptonic Kaon decays and K → ππ(π). July 1996 Invited talk presented at the “Workshop on K Physics,” Orsay, France, May 30 — June 4, 1996. To be published in the...

Kaon production cross sections in nucleon-nucleon, nucleon-delta and delta-delta interactions are studied in a boson exchange model. For the latter two interactions, the exchanged pion can be on-mass shell, only contributions due to a virtual pion are included via the Peierls method by taking into account the finite delta width. With these cross sections and also those for pion-baryon interacti...

Future kaon decay programs at BNL and FNAL are discussed. The primary focus of these programs is the measurement of the golden modes, K: -+ n“v~ and K+ -+ m+VD . The observation of K+ -+ T+VD by E787 at BNL is the first step in a series of measurements which will completely determine the unitarity triangle within the kaon system. The next step after E787 in the measurement of B(K+ + n+vfi ) wil...

In understanding the dynamics of kaon-nucleon scattering or the strangeness content of the nucleon using hadronic models, it is important to know the hadronic coupling constants involving the kaons. Among them, gNKΛ and gNKΣ are the most relevant coupling constants. To determine these couplings using the QCD sum rules [1] one can follow two different approaches: a) the two-point function, where...

We quantitatively study dispersion relations giving the phase of a strong scattering amplitude from its momentum dependence. We consider C-odd contributions to neutral kaon scattering (regeneration) where accurate measurements of both amplitudes and phases are available. We find, somewhat surprisingly, that, even including many possibly corrupting effects, the uncertainty is well below 1 . This...

Recent proposals to test Bell's inequalities with entangled pairs of pseudoscalar mesons are reviewed. This includes pairs of neutral kaons or B–mesons and offers some hope to close both the locality and the detection loopholes. Specific difficulties, however, appear thus invalidating most of those proposals. The best option requires the use of kaon regeneration effects and could lead to a succ...

Quantum marking and quantum erasure are discussed for the neutral kaon system. Contrary to other two–level systems, strangeness and lifetime of a neutral kaon state can be alternatively measured via an “active” or a “passive” procedure. This offers new quantum erasure possibilities. In particular, the operation of a quantum eraser in the “delayed choice” mode is clearly illustrated. PACS number...