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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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Deshpande A, Alliegro C, Chaloupka V, Egger J, Gordon HA, Hadley NJ, Herold WD, Kaspar H, Lee AM, Lazarus DM, Lubatti HJ, Ma H, Rehak P, Skukla A, Zeller ME, Zhao T. Determination of the branching ratio of the decay pi 0-->e+e-. Phys Rev Lett 1993; 71:27-30. [PMID: 10054364 DOI: 10.1103/physrevlett.71.27] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Alliegro C, Campagnari C, Chaloupka V, Cooper PS, Egger J, Gordon HA, Hadley NJ, Herold WD, Kaspar H, Lee AM, Lazarus DM, Lubatti HJ, Rehak P, Zeller ME, Zhao T. Study of the decay K+--> pi +e+e-. Phys Rev Lett 1992; 68:278-281. [PMID: 10045851 DOI: 10.1103/physrevlett.68.278] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Lee AM, Alliegro C, Campagnari C, Chaloupka V, Cooper PS, Egger J, Gordon HA, Hadley NJ, Herold WD, Jagel EA, Kaspar H, Lazarus DM, Lubatti HJ, Rehak P, Zeller ME, Zhao T. Improved limit on the branching ratio of K+--> pi + micro+e-. Phys Rev Lett 1990; 64:165-168. [PMID: 10041666 DOI: 10.1103/physrevlett.64.165] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Campagnari C, Alliegro C, Chaloupka V, Cooper PS, Egger J, Gordon HA, Hadley NJ, Herold WD, Jagel EA, Kaspar H, Lazarus DM, Lee AM, Lubatti HJ, Rehak P, Zeller ME. Search for the decay K+--> pi + micro+e-. Phys Rev Lett 1988; 61:2062-2065. [PMID: 10038973 DOI: 10.1103/physrevlett.61.2062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Baker NJ, Gordon HA, Lazarus DM, Polychronakos VA, Rehak P, Tannenbaum MJ, Egger J, Herold WD, Kaspar H, Chaloupka V, Jagel EA, Lubatti HJ, Alliegro C, Campagnari C, Cooper PS, Hadley NJ, Lee AM, Zeller ME. Search for short-lived neutral particles emitted in K+ decay. Phys Rev Lett 1987; 59:2832-2835. [PMID: 10035665 DOI: 10.1103/physrevlett.59.2832] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Snow JM, Axelrod S, Morrison RL, Zeller ME, Lazarus DM, Nicholson H, Thompson JA. Negative-kaon and antiproton production near 700 MeV/c by 28.4-GeV/c protons. Int J Clin Exp Med 1985; 32:11-20. [PMID: 9955982 DOI: 10.1103/physrevd.32.11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [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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