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Sher A, Appel R, Atoyan GS, Bassalleck B, Bergman DR, Cheung N, Dhawan S, Do H, Egger J, Eilerts S, Fischer H, Herold W, Issakov VV, Kaspar H, Kraus DE, Lazarus DM, Lichard P, Lowe J, Lozano J, Ma H, Majid W, Pislak S, Poblaguev AA, Rehak P, Sher A, Thompson JA, Truöl P, Zeller ME. High statistics measurement of the K+-->pi0e+nu (K+e3) branching ratio. Phys Rev Lett 2003; 91:261802. [PMID: 14754040 DOI: 10.1103/physrevlett.91.261802] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2003] [Indexed: 05/24/2023]
Abstract
E865 at the Brookhaven National Laboratory AGS collected about 70 000 K(+)(e3) events to measure the K(+)(e3) branching ratio relative to the observed K+-->pi(+)pi(0), K+-->pi(0)micro(+)nu, and K+-->pi(+)pi(0)pi(0) decays. The pi(0) in all the decays was detected using the e(+)e(-) pair from pi(0)-->e(+)e(-)gamma decay and no photons were required. Using the 2002 Particle Data Group branching ratios for the normalization decays, we obtain BR(K(+)(e3(gamma)))=(5.13+/-0.02(stat)+/-0.09(syst)+/-0.04(norm))%, where K(+)(e3(gamma)) includes the effect of virtual and real photons. This result is approximately 2.3sigma higher than the current Particle Data Group value. Implications for the V(us) element of the CKM matrix, and the matrix's unitarity are discussed.
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Affiliation(s)
- A Sher
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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Poblaguev AA, Appel R, Atoyan GS, Bassalleck B, Bergman DR, Cheung N, Dhawan S, Do H, Egger J, Eilerts S, Herold W, Issakov VV, Kaspar H, Kraus DE, Lazarus DM, Lichard P, Lowe J, Lozano J, Ma H, Majid W, Pislak S, Rehak P, Sher A, Thompson JA, Truöl P, Zeller ME. Experimental study of the radiative decays K+-->mu(+)nue(+)e(-) and K+-->e(+)nue(+)e(-). Phys Rev Lett 2002; 89:061803. [PMID: 12190577 DOI: 10.1103/physrevlett.89.061803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2002] [Indexed: 05/23/2023]
Abstract
Experiment 865 at the Brookhaven Alternating Gradient Synchrotron obtained 410 K+-->e(+)nue(+)e(-) and 2679 K+-->mu(+)nue(+)e(-) events including 10% and 19% background. The branching ratios were measured to be [2.48+/-0.14(stat)+/-0.14(syst)]x10(-8) (m(ee)>150 MeV) and (7.06+/-0.16+/-0.26)x10(-8) (m(ee)>145 MeV), respectively. Results for the decay form factors are presented.
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Affiliation(s)
- A A Poblaguev
- Institute for Nuclear Research of Russian Academy of Sciences, Moscow 117 312, Russia
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Pislak S, Appel R, Atoyan GS, Bassalleck B, Bergman DR, Cheung N, Dhawan S, Do H, Egger J, Eilerts S, Herold W, Issakov VV, Kaspar H, Kraus DE, Lazarus DM, Lichard P, Lowe J, Lozano J, Ma H, Majid W, Poblaguev AA, Rehak P, Sher A, Thompson JA, Truöl P, Zeller ME. New measurement of K(+)(e4) decay and the s-pave pi pi-scattering length a(0)(0). Phys Rev Lett 2001; 87:221801. [PMID: 11736394 DOI: 10.1103/physrevlett.87.221801] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2001] [Revised: 10/01/2001] [Indexed: 05/23/2023]
Abstract
A sample of 4 x 10(5) events from the decay K(+)-->pi(+)pi(-)e(+)nu(e) (K(e4)) has been collected in experiment E865 at the Brookhaven Alternating Gradient Synchrotron. The analysis of these data yields new measurements of the K(e4) branching ratio [(4.11+/-0.01+/-0.11) x 10(-5)], the s-wave pi pi scattering length [a(0)(0) = 0.216+/-0.013(stat)+/-0.004(syst)+/-0.005(theor)], and the form factors F, G, and H of the hadronic current and their dependence on the invariant pi pi mass.
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Affiliation(s)
- S Pislak
- Physik-Institut, Universität Zürich, CH-8057 Zürich, Switzerland
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Appel R, Atoyan GS, Bassalleck B, Bergman DR, Cheung N, Dhawan S, Do H, Egger J, Eilerts S, Fischer H, Herold W, Issakov VV, Kaspar H, Kraus DE, Lazarus DM, Lichard P, Lowe J, Lozano J, Ma H, Majid W, Menzel W, Pislak S, Poblaguev AA, Rehak P, Sher A, Thompson JA, Truöl P, Zeller ME. Search for lepton flavor violation in K+ decays into a charged pion and two leptons. Phys Rev Lett 2000; 85:2877-2880. [PMID: 11005958 DOI: 10.1103/physrevlett.85.2877] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2000] [Indexed: 05/23/2023]
Abstract
A search for lepton flavor violating decays, K+ --> mu+ mu+ pi-, K+ --> e+ e+ pi-, K+ --> pi+ e+ mu-, K+ --> mu+ e+ pi-, and pi0 --> e+ mu-, was performed using the data collected in Experiment E865 at the Brookhaven Alternating Gradient Synchrotron. No signal was found in any of the decay modes. At the 90% confidence level, the branching ratios are less than 3.0x10(-9), 6.4x10(-10), 5. 2x10(-10), 5.0x10(-10), and 3.4x10(-9), respectively.
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Affiliation(s)
- R Appel
- Physics Department, Yale University, New Haven, Connecticut 06511, USA
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Appel R, Atoyan GS, Bassalleck B, Bergman DR, Brown DN, Cheung N, Dhawan S, Do H, Egger J, Eilerts S, Felder C, Fischer H, Gach M, Herold W, Issakov VV, Kaspar H, Kraus DE, Lazarus DM, Leipuner L, Lichard P, Lowe J, Lozano J, Ma H, Majid W, Menzel W, Pislak S. Improved limit on the rate of the decay K+ --> pi(+)&mgr;(+)e(-). Phys Rev Lett 2000; 85:2450-2453. [PMID: 10978079 DOI: 10.1103/physrevlett.85.2450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2000] [Indexed: 05/23/2023]
Abstract
We report results of a search for the lepton-family number violating decay K+-->pi(+)&mgr;(+)e(-) from data collected by experiment E865 in 1996 at the Alternating Gradient Synchroton of Brookhaven National Laboratory. We place an upper limit on the branching ratio at 3.9x10(-11) ( 90% C.L.). Together with results based on data collected in 1995 and an earlier experiment, E777, this result establishes a combined 90% confidence level upper limit on the branching ratio at 2.8x10(-11). We also report a new upper limit on the branching ratio for pi(0)-->&mgr;(+)e(-) of 3.8x10(-10) ( 90% C. L.).
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Affiliation(s)
- R Appel
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 and Physics Department, Yale University, New Haven, Connecticut 06511, USA
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Ma H, Appel R, Atoyan GS, Bassalleck B, Bergman DR, Cheung N, Dhawan S, Do H, Egger J, Eilerts S, Fischer H, Herold W, Issakov VV, Kaspar H, Kraus DE, Lazarus DM, Lichard P, Lowe J, Lozano J, Majid W, Menzel W, Pislak S, Poblaguev AA, Rehak P, Sher A, Thompson JA. New measurement of the rare decay K+ --> pi(+)&mgr;(+)&mgr;(-). Phys Rev Lett 2000; 84:2580-2583. [PMID: 11017274 DOI: 10.1103/physrevlett.84.2580] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/1999] [Indexed: 05/23/2023]
Abstract
More than 400 K+-->pi(+)&mgr;(+)&mgr;(-) events were observed in a rare K+ decay experiment at the Brookhaven Alternating Gradient Synchrotron. Normalized to the K+-->pi(+)pi(+)pi(-) decay, the branching ratio is determined to be [9.22+/-0.60(stat)+/-0. 49(syst)]x10(-8). This branching ratio and the &mgr;&mgr; mass spectrum is in very good agreement with the measurement of the K+-->pi(+)e(+)e(-) decay, but deviates significantly from the previous measurement.
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Affiliation(s)
- H Ma
- Brookhaven National Laboratory, Upton, New York 11973, USA
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Abstract
Fabrication and testing of a kinoform filter is described, for use in a real-time incoherent optical processor designed for track recognition in high-energy physics experiments. Composition of the filter as a mosaic of kinoforms with different random diffusers improves the quality of the restoration.
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Affiliation(s)
- P Ambs
- Universite de Haute Alsace, Institut des Sciences Exactes et Appliquees, 6809:3 Mulhouse CEI)EX, France
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Thompson JA, Cleland WE, Cooper WE, Dris M, Engels E, Herbert ML, Kraus DE, Lowenstein D. Studies in the BNL 21-GeV/cnegative-hyperon beam. II. Leptonic decays ofΞandΣ. Int J Clin Exp Med 1980. [DOI: 10.1103/physrevd.21.25] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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