Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics (2008)
Abat, E., Abbott, B., Abdallah, J., Abdelalim, A. A., Abdesselam, A., ...
A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance...
Search for Charged Higgs Bosos in $e^{+}e^{-}$ Collisions at $\sqrts{s}$ = 189-209 GeV (2008)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
A search is made for charged Higgs bosons predicted by Two-Higgs-Doublet extensions of the Standard Model (2HDM) using electron-positron collision data collected by the OPAL experiment at...
Search for Charged Higgs Bosos in e+e- Collisions at sqrts(s) = 189-209 GeV (2008)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
A search is made for charged Higgs bosons predicted by Two-Higgs-Doublet extensions of the Standard Model (2HDM) using electron-positron collision data collected by the OPAL experiment at...
Ackerstaff, K, Alexander, G, Allison, J, Altekamp, N, Anderson, K J, Anderson, S, ...
The inclusive production of prompt photons with energy above 10 GeV is measured using the OPAL detector in hadronic Z^0 decays at LEP. In contrast to previous measurements, the prompt photons were...
Measurement of f(c -> D^*+ X), f(b -> D^*+ X) and Gamma_cc(bar)/Gamma_had using D^*+/- Mesons (2008)
Al, K Ackerstaff Et, Ackerstaff, K, Alexander, G, Allison, J, Altekamp, N, Anderson, K J, ...
The production rates of D^*+/- mesons in charm and bottom events at centre-of-mass energies of about 91 GeV and the partial width of primary cc(bar) pairs in hadronic Z^0 decays have been measured at...
A Measurement of the B_s^0 Lifetime using Reconstructed D_s^- Mesons (2008)
Al, K Ackerstaff Et, Ackerstaff, K, Alexander, G, Allison, J, Altekamp, N, Anderson, K J, ...
We report a measurement of the B^0_s meson lifetime from B_s^0 -> D^-_s X decays, where D_s^- mesons are reconstructed in the D_s^- -> phi pi^- and D_s^- -> K^{*0} K^- decay channels. From...
Al, K Ackerstaff Et, Alexander, G, Allison, J, Altekamp, N, Anderson, K J, Anderson, S, ...
Production of events with hadronic and leptonic final states has been measured in e^+e^- collisions at centre-of-mass energies of 130-172 GeV, using the OPAL detector at LEP. Cross-sections and...
Measurement of the $e^+ e^- \to W^+ W^-$ cross section and W decay branching fractions at LEP (2007)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
From a total data sample of 701.1 pb^-1 recorded with e+e- centre-of-mass energies of sqrt = 161-209 GeV with the OPAL detector at LEP, 11693 W-pair candidate events are selected. These data are used...
Bose-Einstein study of position-momentum correlations of charged pions in hadronic Z0 decays (2007)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
A study of Bose-Einstein correlations in pairs of identically charged pions produced in e+e- annihilations at the Z0 peak has been performed for the first time assuming a non-static emitting source....
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
A search is performed for Higgs bosons decaying into invisible final states, produced in association with a Zo boson in e+e- collisions at energies between 183 and 209 GeV. The search is based on...
Search for Dirac Magnetic Monopoles in e+e- Collisions with the OPAL Detector at LEP2 (2007)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
This letter describes a direct search for pair produced magnetic monopoles in e+e- collisions. The analysis is based on 62.7 pb^-1 of data collected with the OPAL detector at an average...
Inclusive Jet Production in Photon-Photon Collisions at $\sqrt^{s}$ee from 189 to 209 GeV (2007)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
Inclusive jet production (e+e- -> e+e- +jet+X) is studied in collisions of quasi-real photons radiated by the LEP beams at e+e- centre-of-mass energies sqrt see from 189 to 209 GeV. Jets are...
Inclusive Production of Charged Hadrons in Photon-Photon Collisions (2006)
Abbiendi, G, Åkesson, P F, De Roeck, A, Zivkovic, L, Zer-Zion, D, Yamashita, S, ...
The inclusive production of charged hadrons in the collisions of quasi-real photons e+e- -> e+e- +X has been measured using the OPAL detector at LEP. The data were taken at e+e- centre-of-mass...
Inclusive Production of Charged Hadrons in Photon-Photon Collisions (2006)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K, ...
The inclusive production of charged hadrons in the collisions of quasi-real photons e+e- -> e+e- +X has been measured using the OPAL detector at LEP. The data were taken at e+e- centre-of-mass...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
This paper describes a topological search for an invisibly decaying Higgs boson,H, produced via the Bjorken process (e+e- -> HZ). The analysis is based on data recorded using the OPAL detector at LEP...
Search for neutral MSSM Higgs bosons at LEP (2006)
Achard, P., Adriani, O., Aguilar-Benítez, M., Alcaraz, J., Alemanni, G., Allaby, J., ...
The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric Standard Model (MSSM). The data of the four...
Search for neutral MSSM Higgs bosons at LEP (2006)
Achard, P., Adriani, O., Aguilar-Benítez, M., Alcaraz, J., Alemanni, G., Allaby, J., ...
The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric Standard Model (MSSM). The data of the four...
Search for neutral MSSM Higgs bosons at LEP (2006)
Achard, P., Adriani, O., Aguilar-Benítez, M., Alcaraz, J., Alemanni, G., Allaby, J., ...
The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric Standard Model (MSSM). The data of the four...
QCD coherence and correlations of particles with restricted momenta in hadronic Z decays (2006)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
QCD coherence effects are studied based on measurements of correlations of particles with either restricted transverse momenta, pT
QCD coherence and correlations of particles with restricted momenta in hadronic Z decays (2006)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
QCD coherence effects are studied based on measurements of correlations of particles with either restricted transverse momenta, pT
Precision Electroweak Measurements on the Z Resonance (2006)
Schael, S, Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, ...
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...
Precision Electroweak Measurements on the Z Resonance (2006)
Schael, S, Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, ...
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...
Search for Neutral MSSM Higgs Bosons at LEP (2006)
Schael, S, Zivkovic, L, Achard, P, Adriani, O, Aguilar-Benítez, M, Alcaraz, J, ...
The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric Standard Model (MSSM). The data of the four...
Search for Neutral MSSM Higgs Bosons at LEP (2006)
Schael, S, Achard, P, Adriani, O, Aguilar-Benítez, M, Alcaraz, J, Alemanni, G, ...
The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric Standard Model (MSSM). The data of the four...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
Data from e+e- annihilation into hadrons at centre-of-mass energies between 91 GeV and 209 GeV collected with the OPAL detector at LEP, are used to study the four-jet rate as a function of the Durham...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
Data from e+e- annihilation into hadrons at centre-of-mass energies between 91 GeV and 209 GeV collected with the OPAL detector at LEP, are used to study the four-jet rate as a function of the Durham...
Search for neutral MSSM Higgs bosons at LEP (2006)
Schael, S., Barate, R., Bruneliere, R., De Bonis, I., Decamp, D., Goy, C., ...
The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric standard model (MSSM). The data of the four...
Colour reconnection in $e^{+}e^{-}\to W^{+}W^{-}$ at $\sqrt{s}$ = 189 - 209 GeV$ (2005)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
The effects of the final state interaction phenomenon known as colour reconnection are investigated at centre-of-mass energies in the range $\sqrt{s}~ 189-209 GeV using the OPAL detector at LEP....
Measurement of the mass and width of the W boson (2005)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
The mass and width of the W boson are measured using e+e- -> W+W- events from the data sample collected by the OPAL experiment at LEP at centre-of-mass energies between 170 GeV and 209 GeV. The mass...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Searches were performed for topologies predicted by gauge-mediated Supersymmetry breaking models (GMSB). All possible lifetimes of the next-to-lightest SUSY particle (NLSP), either the lightest...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Searches were performed for topologies predicted by gauge-mediated Supersymmetry breaking models (GMSB). All possible lifetimes of the next-to-lightest SUSY particle (NLSP), either the lightest...
Determination of $\alpha_{s}$ using Jet Rates at LEP with the OPAL detector (2005)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
Hadronic events produced in e+e- collisions by the LEP collider and recorded by the OPAL detector were used to form distributions based on the number of reconstructed jets. The data were collected...
Determination of $\alpha_{s}$ using Jet Rates at LEP with the OPAL detector (2005)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
Hadronic events produced in e+e- collisions by the LEP collider and recorded by the OPAL detector were used to form distributions based on the number of reconstructed jets. The data were collected...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
For the first time at LEP the production of prompt photons is studied in the collisions of quasi-real photons using the OPAL data taken at e+e- centre-of-mass energies between 183 GeV and 209 GeV....
Measurement of the mass of the Z boson and the energy calibration of LEP (2005)
Arnaudon, L., Assmann, R., Billan, J., Birr, W., Blondel, A., Bobbink, G., ...
Measurement of the mass of the Z boson and the energy calibration of LEP (2005)
Arnaudon, L., Assmann, R., Billan, J., Birr, W., Blondel, A., Bobbink, G., ...
Measurement of the mass of the Z boson and the energy calibration of LEP (2005)
Arnaudon, L., Assmann, R., Billan, J., Birr, W., Blondel, A., Bobbink, G., ...
Measurement of the running of the QED coupling in small-angle Bhabha scattering at LEP (2005)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
Using the OPAL detector at LEP, the running of the effective QED coupling alpha(t) is measured for space-like momentum transfer through its effect on the angular spectrum of small-angle Bhabha...
Measurement of the running of the QED coupling in small-angle Bhabha scattering at LEP (2005)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Anagnostou, G, Anderson, K J, ...
Using the OPAL detector at LEP, the running of the effective QED coupling alpha(t) is measured for space-like momentum transfer through its effect on the angular spectrum of small-angle Bhabha...
Neutral heavy lepton analysis (2005)
Akrawy, M Z, Alexander, Gideon, Allison, J, Allport, P P, Anderson, K J, Armitage, J C, ...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
A study of Z-boson pair production in e+e- annihilation at center-of-mass energies between 190 GeV and 209 GeV is reported. Final states containing only leptons, (l+l-l+l- and l+l-nn), quark and...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
A study of Z-boson pair production in e+e- annihilation at center-of-mass energies between 190 GeV and 209 GeV is reported. Final states containing only leptons, (l+l-l+l- and l+l-nn), quark and...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
We have studied hadronic events from e+e- annihilation data at centre-of-mass energies from 91 to 209 GeV. We present distributions of event shape observables and their moments at each energy and...
Measurement of $R_b$ in $e^+ e^-$ Collisions at 182 - 209 GeV (2004)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Measurements of Rb, the ratio of the bbbar cross-section to the qqbar cross- section in e+e- collisions, are presented. The data were collected by the OPAL experiment at LEP at centre-of-mass...
Search for Radions at LEP2 (2004)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
A new scalar resonance, called the radion, with couplings to fermions and bosons similar to those of the Higgs boson, is predicted in the framework of Randall-Sundrum models, proposed solutions to...
Determination of the LEP Beam Energy using Radiative Fermion-pair Events, 2004 (2004)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
We present a determination of the LEP beam energy using "radiative return" fermion-pair events recorded at centre-of-mass energies from 183 GeV to 209 GeV. We find no evidence of a disagreement...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Upper limits on the cross-section of the pair-production process e+e- -> h0A0 assuming 100% decays into hadrons, are derived from a new search for the h0A0 -> hadrons topology, independent of the...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Events with a final state consisting of two or more photons and large missing transverse energy have been observed in e+e- collisions at centre-of-mass energies in the range 192 - 209 GeV using the...
A Step Towards A Computing Grid For The LHC Experiments: ATLAS Data Challenge 1 (2004)
Sturrock, R, Bischof, R, Epp, B, Ghete, V M, Kuhn, D, Mello, A G, ...
The ATLAS Collaboration at CERN is preparing for the data taking and analysis at the LHC that will start in 2007. Therefore, a series of Data Challenges was started in 2002 whose goals are the...
Search for neutral Higgs bosons in CP-conserving and CP-violating MSSM scenarios (2004)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
This report summarizes the final results from the OPAL collaboration on searches for neutral Higgs bosons predicted by the Minimal Supersymmetric Standard Model (MSSM). CP-conserving and for the...
A step towards a computing grid for the LHC experiments: ATLAS Data Challenge 1 (2004)
Sturrock, R., Bischof, R., Epp, B., Ghete, V.M., Kuhn, D., Mello, A.G., ...
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Flavour inclusive, udsc and b fragmentation functions in unbiased jets, and flavour inclusive, udsc, b and gluon fragmentation functions in biased jets are measured in e+e- annihilations from data...
Measurement of the Strange Spectral Function in Hadronic $\tau$ Decays (2004)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Tau Lepton decays with open strangeness in the final state are measured with the OPAL detector at LEP to determine the strange hadronic spectral function of the tau lepton. The decays tau- ->...
Study of Bose-Einstein Correlations in $e^{+}e^{-}\to W^{+}W^{-}$ events at LEP (2004)
Abbiendi, G, Ainsley, C, Åkesson, T, Alexander, G, Allison, J, Amaral, P, ...
Bose-Einstein correlation between like-sign charged-particle pairs in e+e- -> W+W- events recorded with the OPAL detector at LEP at centre-of-mass energies between 183 GeV and 209 GeV are studied....
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Anomalous quartic couplings between the electroweak gauge bosons may contribute to the vv gamma gamma and qq gamma gamma final states produced in e+e- collisions. This analysis uses the LEP2 OPAL...
Search for Chargino and Neutralino Production at $\sqrt{s}$ = 192-209 GeV at LEP (2004)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Approximately 438 pb-1 of e+e- data from the OPAL detector, taken with the LEP collider running at centre-of-mass energies of 192-209 Gev, are analyzed to search for evidence of chargino pair...
W Boson Polarisation at LEP2 (2003)
Abbiendi, G, Ainsley, C, Åkesson, P F, Alexander, G, Allison, J, Amaral, P, ...
Elements of the spin density matrix for W bosons in e+e- -> W+W- -> qqln events are measured from data recorded by the OPAL detector at LEP. This information is used calculate polarised differential...