|
1
|
Rajaram D, Burnstein RA, Chakravorty A, Chan A, Chen YC, Choong WS, Clark K, Dukes EC, Durandet C, Felix J, Gidal G, Gu P, Gustafson HR, Ho C, Holmstrom T, Huang M, James C, Jenkins CM, Kaplan DM, Lederman LM, Leros N, Longo MJ, Lopez F, Lu LC, Luebke W, Luk KB, Nelson KS, Park HK, Perroud JP, Rubin HA, Teng PK, Volk J, White CG, White SL, Zyla P. Search for the lepton-number-violating decay Xi(-)-->pmu(-)mu(-). Phys Rev Lett 2005; 94:181801. [PMID: 15904358 DOI: 10.1103/physrevlett.94.181801] [Citation(s) in RCA: 1] [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: 12/01/2004] [Indexed: 05/02/2023]
Abstract
A sensitive search for the lepton-number-violating decay Xi(-)-->pmu(-)mu(-) has been performed using a sample of approximately 10(9) Xi(-) hyperons produced in 800 GeV/c p-Cu collisions. We obtain B(Xi(-)-->pmu(-)mu(-))<4.0x10(-8) at 90% confidence, improving on the best previous limit by 4 orders of magnitude.
Collapse
Affiliation(s)
- D Rajaram
- Illinois Institute of Technology, Chicago, IL 60616, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
|
2
|
White CG, Burnstein RA, Chakravorty A, Chan A, Chen YC, Choong WS, Clark K, Dukes EC, Durandet C, Felix J, Gidal G, Gu P, Gustafson HR, Ho C, Holmstrom T, Huang M, James C, Jenkins CM, Kaplan DM, Lederman LM, Leros N, Longo MJ, Lopez F, Lu LC, Luebke W, Luk KB, Nelson KS, Park HK, Perroud JP, Rajaram D, Rubin HA, Teng PK, Volk J, White SL, Zyla P. Search for DeltaS = 2 nonleptonic hyperon decays. Phys Rev Lett 2005; 94:101804. [PMID: 15783474 DOI: 10.1103/physrevlett.94.101804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Indexed: 05/24/2023]
Abstract
A sensitive search for the rare decays Omega(-)--> Lambdapi(-) and Xi(0)--> ppi(-) has been performed using data from the 1997 run of the HyperCP (Fermilab E871) experiment. Limits on other such processes do not exclude the possibility of observable rates for |DeltaS| = 2 nonleptonic hyperon decays, provided the decays occur through parity-odd operators. We obtain the branching-fraction limits B(Omega(-)-->Lambdapi(-)) < 2.9 x 10(-6) and B(Xi(0)--> ppi(-)) < 8.2 x 10(-6), both at 90% confidence level.
Collapse
Affiliation(s)
- C G White
- Illinois Institute of Technology, Chicago, Illinois 60616, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
|
3
|
Park HK, Burnstein RA, Chakravorty A, Chen YC, Choong WS, Clark K, Dukes EC, Durandet C, Felix J, Fu Y, Gidal G, Gustafson HR, Holmstrom T, Huang M, James C, Jenkins CM, Jones T, Kaplan DM, Lederman LM, Leros N, Longo MJ, Lopez F, Lu LC, Luebke W, Luk KB, Nelson KS, Perroud JP, Rajaram D, Rubin HA, Volk J, White CG, White SL, Zyla P. Evidence for the decay sigma+ --> pmu+ mu-. Phys Rev Lett 2005; 94:021801. [PMID: 15698162 DOI: 10.1103/physrevlett.94.021801] [Citation(s) in RCA: 3] [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: 11/03/2004] [Indexed: 05/24/2023]
Abstract
We report the first evidence for the decay Sigma(+)-->pmu(+)mu(-) from data taken by the HyperCP (E871) experiment at Fermilab. Based on three observed events, the branching ratio is B(Sigma(+)-->pmu(+)mu(-))=[8.6(+6.6)(-5.4)(stat)+/-5.5(syst)]x10(-8). The narrow range of dimuon masses may indicate that the decay proceeds via a neutral intermediate state, Sigma(+)-->pP(0),P0-->mu(+)mu(-) with a P0 mass of 214.3+/-0.5 MeV/c(2) and branching ratio B(Sigma(+)-->pP(0),P0-->mu(+)mu(-))=[3.1(+2.4)(-1.9)(stat)+/-1.5(syst)]x10(-8).
Collapse
Affiliation(s)
- H K Park
- University of Michigan, Ann Arbor, Michigan 48109, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
|
4
|
Holmstrom T, Leros N, Burnstein RA, Chakravorty A, Chan A, Chen YC, Choong WS, Clark K, Dukes EC, Durandet C, Felix J, Fu Y, Gidal G, Gu P, Gustafson HR, Ho C, Huang M, James C, Jenkins CM, Jones T, Kaplan DM, Lederman LM, Longo MJ, Lopez F, Lu LC, Luebke W, Luk KB, Nelson KS, Park HK, Perroud JP, Rajaram D, Rubin HA, Teng PK, Volk J, White CG, White SL, Zyla P. Search for CP violation in charged-Xi and Lambda hyperon decays. Phys Rev Lett 2004; 93:262001. [PMID: 15697968 DOI: 10.1103/physrevlett.93.262001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Indexed: 05/24/2023]
Abstract
We have compared the p and p angular distributions in 117 x 10(6) Xi- -->Lambdapi- -->ppi-pi- and 41 x 10(6) Xi+ -->Lambda pi+ -->p pi+pi+ decays using a subset of the data from the HyperCP experiment (E871) at Fermilab. We find no evidence of CP violation, with the direct-CP-violating parameter AXiLambda identical with (alphaXialphaLambda-alpha Xialpha Lambda)/(alphaXialphaLambda+alphaXialphaLambda)=[0.0+/-5.1(stat)+/-4.4(syst)] x 10(-4).
Collapse
Affiliation(s)
- T Holmstrom
- University of Virginia, Charlottesville, Virginia 22904, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
|
5
|
Park HK, Burnstein RA, Chakravorty A, Chan A, Chen YC, Choong WS, Clark K, Dukes EC, Durandet C, Felix J, Gidal G, Gu P, Gustafson HR, Ho C, Holmstrom T, Huang M, James C, Jenkins CM, Kaplan DM, Lederman LM, Leros N, Longo MJ, Lopez F, Lu L, Luebke W, Luk KB, Nelson KS, Perroud JP, Rajaram D, Rubin HA, Teng PK, Volk J, White C, White S, Zyla P. Observation of the decay K- --> pi(-)mu(+)mu(-) and measurements of the branching ratios for K+/- --> pi(+/-)mu(+)mu(-). Phys Rev Lett 2002; 88:111801. [PMID: 11909394 DOI: 10.1103/physrevlett.88.111801] [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: 10/09/2001] [Indexed: 05/23/2023]
Abstract
Using data collected with the HyperCP (E871) spectrometer during the 1997 fixed-target run at Fermilab, we report the first observation of the decay K--->pi(-)mu(+)mu(-) and new measurements of the branching ratios for K+/--->pi(+/-)mu(+)mu(-). By combining the branching ratios for the decays K+-->pi(+)mu(+)mu(-) and K--->pi(-)mu(+)mu(-), we measure Gamma(K+/--->pi(+/-)mu(+)mu(-))/Gamma(K+/--->all) = (9.8+/-1.0+/-0.5)x10(-8). The CP asymmetry between the rates of the two decay modes is [Gamma(K+-->pi(+)mu(+)mu(-))-Gamma(K--->pi(-)mu(+)mu(-))]/[Gamma(K+-->pi(+)mu(+)mu(-))+Gamma(K--->pi(-)mu(+)mu(-))] = -0.02+/-0.11+/-0.04.
Collapse
Affiliation(s)
- H K Park
- University of Michigan, Ann Arbor, Michigan 48109, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|