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CP violation in neutral kaon decays

Description: A brief review of the theoretical status of CP violation in decays of neutral kaons is presented. We focus on three important topics: {epsilon}, {epsilon}`/{epsilon} and K{sub L}{yields}{pi}{sup 0}{nu}{anti {nu}}.
Date: May 1, 1997
Creator: Buchalla, G.
Partner: UNT Libraries Government Documents Department

Status of the KTeV experiment at Fermilab

Description: The KTeV experiment is a fixed target experiment at Fermilab. Its primary goal is the search for direct CP violation in the decay of neutral kaons. Its current status and some preliminary results will be discussed.
Date: October 1, 1997
Creator: Ben-David, R. & Collaboration, KTeV
Partner: UNT Libraries Government Documents Department

Review of K$sup 0$ decays

Description: From meeting of the division of particles and fields; Berkeley, California, USA (13 Aug 1973). A review is given of selected topics in K/sup 0/ decays for which recent results have led to substantial progress and/or cortroversy. (auth)
Date: August 1, 1973
Creator: Nygren, D.R.
Partner: UNT Libraries Government Documents Department

Physics prospects of the KTeV experiment at Fermilab

Description: KTeV is a new Fermilab fixed target experiment which will search for direct CP violation in the neutral kaon system. In addition, we will make precision measurements of other CP and CPT violating parameters and make high sensitivity studies of rare kaon decays. The detector has been commissioned and is currently taking data. The physics goals and detector performance are presented. 12 refs., 1 fig.
Date: October 1, 1996
Creator: Whitmore, J. & Collaboration, KTeV
Partner: UNT Libraries Government Documents Department

Absolute Decay Rate from K<sub>2</sub><sup>0</sup>→π<sup>+</sup> + π<sup>-</sup> + π<sup>0</sup> and the barDELTA I over→bar = 1/2 Rule

Description: In this letter the author describes a measurement of the absolute decay rate {Gamma}{sub 2}({+-}0) {approx_equal} {Gamma}(K{sub 2}{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}). The result is based on 16 events of the type {pi}{sup -} p {yields} {Lambda}K{sup 0} followed by {Lambda} {yields} p{pi}{sup -} and K{sub 2}{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}, and 2608 double-vec events {pi}{sup -} p {yields} {Lambda}K{sup 0} with {Lambda} {yields} p{pi}{sup -} and K{sub 1}{sup 0} {yields} {pi}{sup +}{pi}{sup -}.
Date: February 4, 1964
Creator: Stern, Donald; Binford, Thomas O.; Lind, V. Gordon; Anderson, Jared A.; Crawford, Jr, Frank S. & Golden, Robert L.
Partner: UNT Libraries Government Documents Department

Radiative corrections to the decays K{sub L}{sup 0} {r_arrow} e{sup +}e{sup {minus}} and K{sub L}{sup 0} {r_arrow} {mu}{sup +} {mu}{sup {minus}}

Description: The authors calculate the rates and lepton ({ell}) invariant mass distributions for decays of the form 0{sup {minus}+} {r_arrow} {ell}{sup +}{ell}{sup {minus}}{gamma}, which are important radiative corrections to the purely leptonic decays 0{sup {minus}+} {r_arrow} {ell}{sup +}{ell}{sup {minus}}. The approach uses the loop diagrams which arise by including the two photon intermediate state and they retain the imaginary parts of the loops--a radiative extension of the unitarity bound for the process. These results are compared with those obtained using a model in which the meson couples directly to the leptons.
Date: December 31, 1998
Creator: Dicus, D.A. & Repko, W.W.
Partner: UNT Libraries Government Documents Department

The K{sub L} {yields} {pi}{sup 0}{nu}{anti {nu}} decay beyond the Standard Model

Description: The K{sub L} {yields} {pi}{sup 0}{nu}{anti {nu}} decay is analyzed in a model independent way. When lepton flavor is conserved, this decay mode is a manifestation of CP violating interference between mixing and decay. Consequently, a theoretically clean relation between the measured rate and electroweak parameters holds in any given model.
Date: April 1, 1997
Creator: Grossman, Y.
Partner: UNT Libraries Government Documents Department

K{sub s} K{sub s} System at 800 GeV/c

Description: Results are presented from a partial wave analysis of a sample of centrally produced mesons in the reaction pp {yields} p{sub slow}(K{sub s} K{sub s})p{sub fast} , with 800 GeV/c protons incident on a liquid hydrogen target. The meson system is found to be predominantly S-wave in the mass range between K{sub s} K{sub s} threshold and 1.58 GeV/c{sup 2} . The f{sub 0}(1500) is clearly observed in this region. Above 1.58 GeV/c{sup 2} two solutions are possible, one with mainly S-wave and another with mainly D-wave. This ambiguity prevents a unique determination of the spin of the f{sub J} (1710) meson.
Date: December 1, 1997
Creator: Reyes, M.A. & others, and
Partner: UNT Libraries Government Documents Department

A kaon physics program at the Fermialb Main Injector

Description: In this paper we describe a triad of kaon experiments which will form the foundation of a kaon physics program at Fermilab in the Main Injector era. These three experiments; KAMI, CKM and CPT, span the range of experiment types discussed above. KAMI will use the existing neutral kaon beam and the KTeV detector as the basis of a search for the Standard Model ultra rare decay K{sub L} {yields} {pi}{sup 0}{nu}{anti {nu}} decay mode is by far the theoretically cleanest measurement of the Standard Model parameter responsible for CP violation. CKM will measure the analogous charged kaon decay mode. Together these two experiments will determine the Standard Model contribution to CP violation independent of the B meson sector. The Standard Model parameters controlling CP violation must be observed to be the same in the K and B meson sectors in order to confirm the Standard Model as the sole source of CP violation in nature. CPT is a hybrid beam experiment using a high purity K{sup +} beam to produce a pure K{sub 0} beam in order to search for violation of CPT symmetry at a mass scale up to the Planck mass. CPT also will measure new CP violation parameters to test the Standard Model and search for rare K{sub S} decays. The Fermilab infrastructure for such a physics program largely already exists. The Main Injector will be an existing accelerator by late 1998 with beam properties comparable to any of the previous ``kaon factory`` proposals. The KTeV detector and neutral kaon beamline are unsurpassed in the world and were originally designed to also operate with the 120 GeV Main Injector beam as KAMI. The Fermilab Meson laboratory was originally designed as an area for fixed target experiments using 200 GeV proton beams. The charged kaon beam experiments ...
Date: November 1, 1997
Creator: Cooper, Peter
Partner: UNT Libraries Government Documents Department

Re({epsilon}{prime}/{epsilon})Result from KTeV - An observation of direct-CP violation

Description: Using a subset of data collected in the 1996-97 fixed target run at Fermilab, the authors report the first preliminary measurement on the direct-CP violation from the KTeV experiment. The result is, e{prime}/e = (28.0-4.1) x 10{sup {minus}4}, nearly 7 standard deviations above zero obtained by a blind analysis. This establishes the long-sought direct-CP violation effect in the two-pion system of neutral kaon decays. The experimental technique, data analysis and systematic checks for this measurement are discussed and the comparison with other measurements is also presented.
Date: November 10, 1999
Creator: Hsiung, Yee Bob
Partner: UNT Libraries Government Documents Department

Latest experimental information on {epsilon}{prime}/{epsilon}

Description: The authors review the latest experimental results in search for direct CP-violation by measuring the CP-violating parameters Re({epsilon}{prime}/{epsilon}) in neutral kaon decays. The recent result from Fermilab-KTeV Re({epsilon}{prime}/{epsilon}) = (28.0 {+-} 4.1) x 10{sup {minus}4}, and the new preliminary result from CERN-NA48 Re({epsilon}{prime}/{epsilon}) = (14.0 {+-} 4.3) x 10{sup {minus}4}, are presented. Both experiments, though using very different techniques, have now performed very well by collecting millions of events for all four relevant decay modes of K{sub L,S} to {pi}{sup +}{pi}{sup {minus}} and {pi}{sup 0}{pi}{sup 0} simultaneously. The current world average on this important measurement is Re({epsilon}{prime}/{epsilon}) = 19.3 {+-} 10{sup {minus}4} with a {chi}{sup 2}/ndf = 11.1/5, establishing the existence of direct CP-violation. The experimental status of such crucial measurements and the future prospects are also discussed here.
Date: August 17, 2000
Creator: Hsiung, Yee B.
Partner: UNT Libraries Government Documents Department

Observation of direct-CP violation

Description: Using a subset of data collected in the 1996-97 fixed target run at Fermilab, the authors report the first preliminary measurement on the direct-CP violation from the KTeV experiment. The result is, e{prime}/e = (28.0-4.1) x 10{sup {minus}4}, nearly 7 standard deviations above zero obtained by a blind analysis. This establishes the long-sought direct-CP violation effect in the two-pion system of neutral kaon decays. The experimental technique, data analysis and systematic checks for this measurement are discussed and the comparison with other measurements is also presented.
Date: November 10, 1999
Creator: Hsiung, Yee Bob
Partner: UNT Libraries Government Documents Department

Search for the decay B^0 --> K^0_S K^0_S K^0_L

Description: The authors present the first search for the decay B{sup 0} {yields} K{sub S}{sup 0} K{sub S}{sup 0} K{sub L}{sup 0} using a data sample of 232 million B{bar B} pairs. They find no statistically significant evidence for the non-resonant component of this decay. Our central value for the branching fraction, assuming the tru Dalitz distribution is uniform and excluding the {phi} resonance, is {Beta}(B{sup 0} {yields} K{sub S}{sup 0} K{sub S}{sup 0} K{sub L}{sup 0}) = (2.4{sub -2.5}{sup +2.7} {+-} 0.6) x 10{sup -6} where the errors are statistical and systematic, respectively. They set a single-side Bayesian upper limit of {Beta}(B{sup 0} {yields} K{sub S}{sup 0} K{sub S}{sup 0} K{sub L}{sup 0}) &lt; 6.4 x 10{sup -6} at 90% confidence level using a uniform prior probability for physical values. Assuming the worst-case true Dalitz distribution, where the signal is entirely in the region of lowest efficiency, the 90% confidence level upper limit is {Beta}(B{sup 0} {yields} K{sub S}{sup 0} K{sub S}{sup 0} K{sub L}{sup 0}) &lt; 14 x 10{sup -6}.
Date: June 27, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Charmless Quasi-Two-Body Modes at BaBar

Description: We present results for measurements of B{sup 0} meson decays to charmless final states {eta}K{sup 0}, {eta}{omega}, a{sub 1}{sup +}(1260){pi}{sup -} with a{sub 1}{sup +}(1260) {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -}, {rho}{sup 0}K{sub S}{sup 0}, K{sub S}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0}, and of B{sup +} to {eta}{rho}{sup +} and {eta}{prime}{pi}{sup +}. Analyses are based on data taken with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC.
Date: October 19, 2005
Creator: Palombo, F. & /INFN, Milan
Partner: UNT Libraries Government Documents Department

Study of Multi-body Charmless B Decays with the BaBar Experiment

Description: The authors report recent measurements of charmless B decays to the final states K{sup +}K{sup +}K{sup -}, {phi}{phi}K, {eta}'{eta}'K, M{sub S}{sup 0}K{sub S}{sup 0}K{sub L}{sup 0}, {bar {Lambda}}p{pi}{sup +}, K*{sup +}h{sup +}h{sup -} and KX(inclusive). The results were obtained using a data sample of up to 288.5 fb{sup -1} recorded by the BABAR detector at the PEP-II asymmetric B factory at SLAC.
Date: October 18, 2006
Creator: Latham, Thomas E.
Partner: UNT Libraries Government Documents Department

Recent Results from Fermilab E690

Description: Partial wave analysis results of centrally produced mesons in the reaction pp {yields} P{sub slow}(X)P{sub fast}, with 800 GeV/c protons incident on a liquid hydrogen target are presented. In the reactions considered in this paper the (X) system decays into: a) K{sup 0}{sub s}K{sup {+-}}{pi}{sup {-+}}, b) K{sub s}K{sub s}, and c) {pi}{sup +}{pi}{sup -}.
Date: January 1, 1998
Creator: Berisso, M. C.; Christian, D. C.; Felix, J.; Gara, A.; Gottschalk, E.; Gutierrez, G. et al.
Partner: UNT Libraries Government Documents Department

Overview of rare K decays

Description: The status and future prospects of searches for and studies of forbidden and highly suppressed K decays are reviewed. Here the author discusses three areas of recent activity in rare K decay. These are lepton-flavor violating decays, which are entirely forbidden in the Standard Model, K{sub S} {yields} {pi}{sup +}{pi}{sup {minus}}{pi}{sup 0}, which is of interest from the point of view of CP-violation, and `one loop` decays of the form K{sup 0,{+-}} {yields} ({pi}{sup 0,{+-}})l{bar l}, that can throw light on Standard Model CP-violation and determine parameters such as V{sub td}.
Date: May 1, 1995
Creator: Littenberg, L.
Partner: UNT Libraries Government Documents Department

Measurement of B{sup 0}/Bbar{sup 0} {right arrow}J/{psi} K(0 over s) decay asymmetry using same-side b-flavor tagging

Description: We present a measurement of the time-dependent asymmetry in the rate for {anti B}{sup 0} versus B{sup 0} decays to J/{psi}K{sup 0}{sub s}. The data sample consists of 198 {+-} 17 B{sup 0}/{anti B}{sup 0} decays collected by the CDF detector in p{anti p} collisions at the Fermilab Tevatron, where the initial b flavor has been determined by a same-side flavor tagging technique. This asymmetry is interpreted in the Standard Model as a measurement of the CP-violation parameter sin(2{beta}). Our analysis results in sin(2{beta}) = 1:8 {+-} 1:1(stat) {+-} 0:3(syst).
Date: October 1, 1998
Creator: Tseng, J.
Partner: UNT Libraries Government Documents Department

Rare and forbidden kaon decays at the AGS

Description: An overview of the Rare Kaon Decay program at the AGS is presented, with particular emphasis on the three major experiments currently running and analyzing data. A brief overview of earlier kaon decay experiments and of the AGs performance improvements is also provided. This review concludes with a discussion of proposed and developing experiments planned to run in the year 2000 and beyond (AGS-2000).
Date: December 9, 1997
Creator: Kettell, S.
Partner: UNT Libraries Government Documents Department