| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
- Abreu, P, et al.
(författare)
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A measurement of the Tau topological branching ratios
- 2001
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Ingår i: EUROPEAN PHYSICAL JOURNAL C. - : SPRINGER-VERLAG. - 1434-6044. ; 20:4, s. 617-637
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Tidskriftsartikel (refereegranskat)abstract
- Using data collected in the DELPHI detector at LEP-1, measurements of the inclusive T branching ratios for decay modes containing one, three, or five charged particles have been performed, giving the following results: B-1 equivalent to B T- (particle)(-)
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| 3. |
- Abreu, P, et al.
(författare)
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Measurement of the mass and width of the W boson in e(+)e(-) collisions at root s=189 GeV
- 2001
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Ingår i: PHYSICS LETTERS B. - : ELSEVIER SCIENCE BV. - 0370-2693. ; 511:2-4, s. 159-177
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Tidskriftsartikel (refereegranskat)abstract
- A measurement of the FV mass and width has been performed by the DELPHI Collaboration using the data collected during 1998. The data sample has an integrated luminosity of 155 pb(-1) and an average centre-of-mass energy of 188.6 GeV. Results are obtained
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| 4. |
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| 5. |
- Abreu, P, et al.
(författare)
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Search for a fermiophobic Higgs at LEP 2
- 2001
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Ingår i: PHYSICS LETTERS B. - : ELSEVIER SCIENCE BV. - 0370-2693. ; 507:1-4, s. 89-103
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Tidskriftsartikel (refereegranskat)abstract
- Higgs bosons predicted by the fermiophobic scenario within Two Higgs Doublers Models were searched for in the data collected by the DELPHI detector at centre-of-mass energies between 189 GeV and 202 GeV, corresponding to a total integrated luminosity of 3
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| 6. |
- Abreu, P, et al.
(författare)
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Search for spontaneous R-parity violation at root s=183 GeV and 189 GeV
- 2001
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Ingår i: PHYSICS LETTERS B. - : ELSEVIER SCIENCE BV. - 0370-2693. ; 502:1-4, s. 24-36
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Tidskriftsartikel (refereegranskat)abstract
- Searches for spontaneous R-parity-violating signals at roots = 183 GeV and roots = 189 GeV have been performed using the 1997 and 1998 DELPHI data, under the assumption of R-parity breaking in the third lepton family. The expected topology for the decay o
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| 7. |
- Abreu, P, et al.
(författare)
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Search for the sgoldstino at root s from 189 to 202 GeV
- 2000
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Ingår i: PHYSICS LETTERS B. - : ELSEVIER SCIENCE BV. - 0370-2693. ; 494:3-4, s. 203-214
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Tidskriftsartikel (refereegranskat)abstract
- A search for the supersymmetric partner of the goldstino, the sgoldstino S, at LEP2 is presented. The production S gamma followed by S decay into two gluons or into two photons was studied at 189-202 GeV LEP centre-of-mass energies. No evidence for the S
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| 8. |
- Abreu, P, et al.
(författare)
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Search for the Standard Model Higgs boson at LEP in the year 2000
- 2001
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Ingår i: PHYSICS LETTERS B. - : ELSEVIER SCIENCE BV. - 0370-2693. ; 499:1-2, s. 23-37
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Tidskriftsartikel (refereegranskat)abstract
- Searches for the Standard Model Higgs boson have been performed in the data collected by the. DELPHI experiment at LEP in the year 2000 at centre-of-mass energies between 200 and 209 GeV corresponding to a total integrated luminosity of 224 pb(-1). No evi
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| 9. |
- Abreu, P, et al.
(författare)
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Single intermediate vector boson production in e(+)e(-) collisions at root s=183 and 189 GeV
- 2001
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Ingår i: PHYSICS LETTERS B. - : ELSEVIER SCIENCE BV. - 0370-2693. ; 515:3-4, s. 238-254
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Tidskriftsartikel (refereegranskat)abstract
- The cross sections for the production of single charged and neutral intermediate vector bosons were measured using integrated luminosities of 52 pb(-1) and 154 pb(-1) collected by the experiment at centre-of-mass energies of 182.6 GeV and 188.6 GeV, respe
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| 10. |
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