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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

CP-Violating solitons in the early universe

Description: Solitons in extensions of the Standard Model can serve as localized sources of CP violation. Depending on their stability properties, they may serve either to create or to deplete the baryon asymmetry. The conditions for existence of a particular soliton candidate, the membrane solution of the two-Higgs model, are presented. In the generic case, investigated by Bachas and Tomaras, membranes exist and are metastable for a wide range of parameters. For the more viable supersymmetric case, it is shown that the present-day existence of CP-violating membranes is experimentally excluded, but preliminary studies suggest that they may have existed in the early universe soon after the electroweak phase transition, with important consequences for the baryon asymmetry of the universe.
Date: July 1, 1997
Creator: Tornkvist, O. & Riotto, A.
Partner: UNT Libraries Government Documents Department

CPand t violation in neutrino oscillations

Description: In this short lecture, we discuss some basic phenomenological aspects of CP and T violation in neutrino oscillation. Using CP/T trajectory diagrams in the bi-probability space, we try to sketch out some essential features of the interplay between the effect of CP/T violating phase and that of the matter in neutrino oscillation.
Date: September 18, 2003
Creator: Minakata, Hisakazu; Nunokawa, Hiroshi & Parke, Stephen
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

Prospects for mixing and CP violation at the Tevatron

Description: The Fermilab p{bar p} Tevatron collider, operating at {radical}s = 1. 8 TeV, is a proficient source of B hadrons. The first collider run, Run I, has clearly proven that B states can be observed cleanly and can be studied in great detail in a hadron collider environment. In this presentation the future of the study of B{bar B} mixing and of CP violation at the Tevatron, with an upgraded machine and detectors, is discussed.
Date: December 1, 1996
Creator: Rijssenbeek, M. & collaborations, The CDF and DO
Partner: UNT Libraries Government Documents Department

Flavor and CP violations from sleptons at the Muon Collider

Description: Supersymmetric theories generally have new flavor and CP violation sources in the squark and slepton mass matrices. They will contribute to the lepton flavor violation processes, such as {mu}{yields}e{gamma}, which can be probed far below the current bound with an intense muon source at the front end of the muon collider. In addition, if sleptons can be produced at the muon collider, the flavor violation can occur at their production and decay, allowing us to probe the flavor mixing structure directly. Asymmetry between numbers of {mu}{sup +}e{sup -} and e{sup +}{mu}{sup -} events will be a sign for CP violation in supersymmetric flavor mixing.
Date: December 1, 1997
Creator: Cheng, H.-C.
Partner: UNT Libraries Government Documents Department

B {0 over d} mixing and CP violation measurements at the Tevatron

Description: We present six time-dependent B<sup>0</sup><sub>d</sub> mixing measurements of {Delta}m<sub>d</sub> from the CDF Run I data. The CDF average is {Delta}m<sub>d</sub> = .494<sup>&plusmn;.026</sup><sub>&plusmn;.026</sub>(ps)<sup>-1</sup>. We also present a measurement of the CP-violating asymmetry sin(2{beta}) using a sample of B<sup>0</sup>/{anti B}<sup>0</sup> {yields} J/{psi} K<sup>0</sup><sub>s</sub> decays and report sin(2{beta}) = .79 <sup>+41</sup><sub>-.44</sub>.
Date: July 27, 1999
Creator: Byrum, K.
Partner: UNT Libraries Government Documents Department

B Decays as a probe of spontaneous cp-violation in SUSY models

Description: We consider phenomenological implications of susy models with spontaneously broken CP-symmetry. In particular, we analyze CP-asymmetries in B decays and find that the predictions of these models are vastly different from those of the SM. These features are common to NMSSM-like models with an arbitrary number of sterile superfields and the MSSM with broken R-parity.
Date: July 8, 1999
Creator: Lebedev, Oleg
Partner: UNT Libraries Government Documents Department

Prospects for cp violation searches at Tevatron

Description: In the near future CP violation measurements will be one of the most crucial test for the Standard Model. Several B factories are going to be built to study these phenomena in the B system. These goals can be achieved also at the Tevatron Collider by the two experiments: CDF and D0. Starting from data collected during Run I the sensitivity expected in Run II is shown.
Date: September 1, 1997
Creator: Lucchesi, D.
Partner: UNT Libraries Government Documents Department

The Measurement of xi'/xi at Fermilab KTeV-E832

Description: The status of the analysis effort for the 25% data sample taken during the Fermilab '96-'97 fixed target run for {epsilon}'/{epsilon} measurement from KTeV is presented here. Detector performance, data statistics, background subtractions, data and monte-carlo comparison for acceptance corrections, as well as the preliminary results on K{sub L}{yields}{pi}{sup 0}{gamma}{gamma} are described in more detail. Prospects for KTeV 99, in the up coming 6 months '99 fixed target run, are also discussed here.
Date: February 15, 1999
Creator: Hsiung, Yee Bob
Partner: UNT Libraries Government Documents Department

CP violation, mixing and rare decays at the Tevatron now and in Run II

Description: We review the status of current B mixing and CP violation measurements from the Fermilab Tevatron. With the existing data sample, the CDF collaboration has made competitive measurements of B{sub d}{sup 0} mixing; set limits on B{sub s}{sup 0} mixing and has begun a direct search of CP violation in the B system through the decay B{sup 0}/{anti B}{sup 0}{yields}J/{psi}K{sub S}{sup 0}. The prospects for future b measurements at the Tevatron, including CP violation, B{sub s}{sup 0} mixing and rare decay searches are discussed.
Date: December 1, 1998
Creator: Pitts, Kevin T.
Partner: UNT Libraries Government Documents Department

Measurement of the cp asymmetry Parameter sin(2{beta}) at CDF

Description: We present a measurement of the time-dependent asymmetry in the rate for {anti }B{sup 0}{sub d} versus B{sup 0}{sub d} decays to J/{psi} K{sup 0}{sub S} . In the context of the Standard Model this is interpreted as a measurement of the CP-violation parameter sin(2{beta}). A total of 198 {+-} 17 B{sup 0}{sub d}/{anti B}{sup 0}{sub d} decays were observed in p{anti p} collisions at ps = 1:8 TeV by the CDF detector at the Fermilab Tevatron. The initial b-flavor is determined by a same side avor tagging technique. Our analysis results in sin(2{beta}) = 1:8 {+-} 1:1(stat) {+-} 0:3(syst).
Date: October 1, 1998
Creator: LeCompte, T. J.
Partner: UNT Libraries Government Documents Department

The pooltable analogy to axion physics

Description: An imaginary character named TSP finds himself in a playroom whose floor is tilted to one side. However, the pooltable in the playroom is horizontal. TSP wonders how this can be. In doing so, he embarks upon an intellectual journey which parallels that which has been travelled during the past two decades by physicists interested in the Strong CP Problem and axion physics.
Date: January 1, 1996
Creator: Sikivie, P.
Partner: UNT Libraries Government Documents Department

A second-generation cosmic axion experiment

Description: An experiment is described to detect dark matter axions trapped in the halo of our galaxy. Galactic axions are converted into microwave photons via the Primakoff effect in a static background field provided by a superconducting magnet. The photons are collected in a high Q microwave cavity and detected by a low noise receiver. The axion mass range accessible by this experiment is 1.3 {minus} 13 {mu}eV. The expected sensitivity will be roughly 50 times greater than achieved by previous experiments in this mass range. The assembly of the detector is well under any at LLNL and data taking will start in mid-1995.
Date: May 1, 1995
Creator: Hagmann, C.; Stoeffl, W. & van Bibber, K.
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

CP nonconservation in p{anti p} {r_arrow} t{anti b}{Chi} at the Tevatron

Description: The reaction p{anti p} {r_arrow} t{anti b}{Chi} is found to be rather rich in exhibiting several different types of CP asymmetries. The spin of the top quark plays an important role. Asymmetries are related to form factors arising from radiative corrections of the t{anti b}W production vertex due to non-standard physics. As illustrations, effects are studied in two Higgs Doublet Models and in Supersymmetric Models; asymmetries up to a few percent may be possible.
Date: June 1996
Creator: Atwood, David; Bar-Shalom, Shaouly; Eilam, Gad & Soni, Amarjit
Partner: UNT Libraries Government Documents Department

Search for new mechanism of CP violation through tau decay and semileptonic decay at hadrons

Description: If CP is violated in any decay process involving leptons it will signify the existence of a new force (called the X boson) responsible for CP violation that may be the key to understanding matter-antimatter asymmetry in the universe. The author discusses the signatures of CP violation in (1) the decay of tau lepton, and (2) the semileptonic decay of {pi}, K, D, B and t particles by measuring the polarization of the charged lepton in the decay. The author discusses how the coupling constants and their phases of the coupling of the X boson to 9 quark vertices and 3 lepton vertices can be obtained through 12 decay processes.
Date: November 1, 1996
Creator: Tsai, Yung Su
Partner: UNT Libraries Government Documents Department

Test of CPT Invariance in B Factories

Description: Feasibility of setting limits on CPT violating parameters for the case of both CP conjugate and semileptonic decays of neutral Bd mesons were examined. For the case of semileptonic final states of neutral Bd meson decays, bounds on CPT violating parameters at the level of few percent can be easily obtained. This sensitivity is better than the similar analysis using the CP conjugate final states of neutral Bd meson decays mainly due to the substantial increase on the statistics.
Date: February 2, 1999
Creator: Yang, Songhoon
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

Experimental study of sin 2 {beta} and sin 2 {alpha}

Description: Detailed measurements of CP violation in B meson decay are on the horizon. Here the author reviews the status of current measurements of sin 2{beta} made at LEP and CDF. These yield an average of sin 2{beta} = 0.82 {+-} 0.39, giving 97% confidence that {beta} is greater than 0, evidence that CP violation occurs in B decay. He reviews predictions for the precision one can expect on sin 2{beta} and sin 2{alpha} in the next few years.
Date: March 7, 2000
Creator: Truschuk, W.
Partner: UNT Libraries Government Documents Department

CPT Results from KTeV

Description: I present several preliminary measurements from KTeV of the fundamental neutral K parameters, and their implications for CPT violation. A new limit is given on the sidereal time dependence of {phi}{sub +-}. The results are based on data collected in 1996-97.
Date: January 14, 2002
Creator: Nguyen, Hogan
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

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