0000000000964926

AUTHOR

A Winhart

Measurement of the radiative K-e3 branching ratio

We present a measurement of the relative branching ratio of the decay KL -> pi e nu gamma (Ke3gamma) with respect to KL-> pi e nu (gamma) (Ke3+Ke3gamma) decay. The result is based on observation of 19 000 Ke3gamma and 5.6 x 10^6 Ke3 decays. The value of the branching ratio is Br(Ke3gamma, Egamma^*>30 MeV,theta(e,gamma)^*>20^o)/Br(Ke3)= (0.964+-0.008+0.011-0.009)%. This result agrees with theoretical predictions but is at variance with a recently published result.

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A measurement of the K-S lifetime

A measurement of the K_S lifetime is presented using data recorded by the NA48 experiment at the CERN-SPS during 1998 and 1999. The K_S lifetime is derived from the ratio of decay time distributions in simultaneous, collinear K_S and K_L beams, giving a result which is approximately independent of the detector acceptance and with reduced systematic errors. The result obtained is tau_S=(0.89598 +- 0.00048 +- 0.00051)x10^(-10) s, where the first error is statistical and the second systematic.

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Search for the decay K-s -> pi(0)e(+)e(-)

Abstract A search for the decay K S →π 0 e + e − has been made using the NA48 detector at the CERN SPS. Using data collected in 1999 during a 40-hour run with a high-intensity KS beam, an upper limit for the branching fraction B (K S →π 0 e + e − ) −7 at 90% confidence level has been obtained.

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The beam and detector of the NA62 experiment at CERN

NA62 is a fixed-target experiment at the CERN SPS dedicated to measurements of rare kaon decays. Such measurements, like the branching fraction of the $K^{+} \rightarrow \pi^{+} \nu \bar\nu$ decay, have the potential to bring significant insights into new physics processes when comparison is made with precise theoretical predictions. For this purpose, innovative techniques have been developed, in particular, in the domain of low-mass tracking devices. Detector construction spanned several years from 2009 to 2014. The collaboration started detector commissioning in 2014 and will collect data until the end of 2018. The beam line and detector components are described together with their early …

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The beam and detector for the NA48 neutral kaon CP violation experiment at CERN

The beam and detector, used for the NA48 experiment, devoted to the measurement of Re (ε{lunate}′ / ε{lunate}), and for the NA48/1 experiment on rare KS and neutral hyperon decays, are described. © 2007 Elsevier B.V. All rights reserved.

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Kaon physics at the CERN-SPS

The NA48/2 and NA62 collaborations report on recent results, current status, and prospects of kaon physics at the CERN-SPS. The NA62 collaborations aims to measure the decay [Formula: see text] with an uncertainty of 10% or better. The NA62 detector and preliminary results from a pilot run in 2014 are presented. In addition, recent results of the NA48/2 collaboration are reported. A search for Dark Photons has been performed in [Formula: see text] decays via the kaon decays [Formula: see text] and [Formula: see text]. No dark photon signal was observed and new upper limits on the mixing parameter [Formula: see text] and the dark photon mass were computed. We also report the first observati…

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