586 citations · 2.1k across the 45 of their papers we have counts for
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Search for Two-Photon Interaction with Axionlike Particles Using High-Repetition Pulsed Magnets and Synchrotron X Rays
T. Inada, T. Yamazaki, T. Namba +12
We report on new results of a search for two-photon interaction with axionlike particles (ALPs). The experiment was carried out at a synchrotron radiation facility using a "light s…
Search for Photon-Photon Elastic Scattering in the X-ray Region
T. Inada, T. Yamaji, S. Adachi +9
We report the first results of a search for real photon-photon scattering using X rays. A novel system is developed to split and collide X-ray pulses by applying interferometric te…
First Millimeter-wave Spectroscopy of the Ground-state Positronium
A. Miyazaki, T. Yamazaki, T. Suehara +7
We report on the first measurement of the Breit-Wigner resonance of the transition from {\it ortho-}positronium to {\it para-}positronium. We have developed an optical system to ac…
Direct Observation of the Hyperfine Transition of the Ground State Positronium
T. Yamazaki, A. Miyazaki, T. Suehara +7
We report the first direct measurement of the hyperfine transition of the ground state positronium. The hyperfine structure between ortho-positronium and para-positronium is about…
Search for CP-violation in Positronium Decay
T. Yamazaki, T. Namba, S. Asai +1
CP-violation in the quark sector has been well established over the last decade, but has not been observed in the lepton sector. We search for CP-violating decay processes in posit…
Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics
The ATLAS Collaboration, G. Aad, E. Abat +2604
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 w…
Inclusive Jet Production in Photon-Photon Collisions at sqrt(s_ee) from 189 to 209 GeV
The OPAL collaboration
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…
Measurement of event shape distributions and moments in e+e- -> hadrons at 91-209 GeV and a determination of alpha_s
The OPAL Collaboration, G. Abbiendi
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…
Search for Stable and Long-Lived Massive Charged Particles in e+e- Collisions at sqrt(s) = 183-209 GeV
The OPAL collaboration
A search for stable and long-lived massive particles of electric charge |Q/e|=1 or fractional charges of 2/3, 4/3, and 5/3 is reported using data collected by the OPAL detector at…
Test of non-commutative QED in the process e+e- -> gamma gamma at LEP
The OPAL collaboration
Non-commutative QED would lead to deviations from the Standard Model depending on a new energy scale Lambda_NC and a unique direction in space defined by two angles eta and xi. Her…
Measurement of Neutral-Current Four-Fermion Production at LEP2
The OPAL collaboration
Four-fermion final states qqbar e+e- and qqbar mu+mu- from neutral-current interactions in e+e- collisions are studied in the OPAL detector at LEP at centre-of-mass energies from 1…
Search for Associated Production of Massive States Decaying into Two Photonsin e+e- Annihilations at sqrt(s) = 88-209 GeV
The OPAL collaboration, G. Abbiendi
A search is performed for production of short-lived particles in e+e- -> XY, with X -> gamma gamma and Y -> ffbar, for scalar X and scalar or vector Y. Model-independent limits in…
Genuine Correlations of Like-Sign Particles in Hadronic Z0 Decays
The OPAL collaboration, G. Abbiendi
Correlations among hadrons with the same electric charge produced in Z0 decays are studied using the high statistics data collected from 1991 through 1995 with the OPAL detector at…
Measurement of the Branching Ratio for the Process b -> tau nu X
The OPAL collaboration, G. Abbiendi
The inclusive branching ratio for the process b -> tau nu X has been measured using hadronic Z decays collected by the OPAL experiment at LEP in the years 1992-2000. The result is:…
Angular Analysis of the Muon Pair Asymmetry at LEP 1
The OPAL collaboration, G. Abbiendi
Data on muon pair production obtained by the OPAL collaboration at centre of mass energies near the Z peak are analysed. Small angular mismatches between the directions of the two…
Production rate of bb(bar) quark pairs from gluons and bb(bar)bb(bar) events in hadronic Z Decays
The OPAL collaboration, G. Abbiendi
The rates are measured per hadronic Z decay for gluon splitting to bb(bar) quark pairs, g_bb, and of events containing two bb(bar) quark pairs, g_4b, using a sample of four-jet eve…
A Measurement of the Rate of Charm Production in W Decays
The OPAL collaboration, G. Abbiendi
Using data recorded at centre-of-mass energies around 183 GeV and 189 GeV with the OPAL detector at LEP, the fundamental coupling of the charm quark to the W boson has been studied…
Measurement of the Mass and Width of the W Boson in e+e- Collisions at 189 GeV
The OPAL collaboration, G. Abbiendi
The mass and width of the W boson are determined in e+e- collisions at LEP using 183 pb^-1 of data recorded at a centre-of-mass energy roots=189 GeV with the OPAL detector. The inv…
Searches for prompt light gravitino signatures in e+e- Collisions at sqrt{s}=189GeV
The OPAL collaboration, G. Abbiendi
Searches for final states expected in models with light gravitinos have been performed, including experimental topologies with multi-leptons with missing energy, leptons and photon…
A measurement of the tau mass and the first CPT test with tau leptons
G. Abbiendi, the OPAL collaboration
We measure the mass of the tau lepton to be 1775.1+-1.6(stat)+-1.0(syst.) MeV using tau pairs from Z0 decays. To test CPT invariance we compare the masses of the positively and neg…
Photonic events with missing energy in e+e- collisions at sqrt(s)=189 GeV
G. Abbiendi, the OPAL collaboration
Photonic events with large missing energy have been observed in e+e- collisions at a centre-of-mass energy of 189GeV using the OPAL detector at LEP. Results are presented for event…
Search for new Physics in rare B Decays
The OPAL collaboration, G. Abbiendi
A search for the decay B+- to K+-K+-pi-+ was performed using data collected by the OPAL detector at LEP. These decays are strongly suppressed in the Standard Model but could occur…
Measurement of the W+W-gamma Cross-section and First direct Limits on Anomalous Electroweak Quartic Gauge Couplings
The OPAL collaboration, G. Abbiendi
A study of W+W- events accompanied by hard photon radiation produced in e+e- collisions at LEP is presented. Events consistent with two on-shell W-bosons and an isolated photon are…
Search for Neutral Higgs Bosons in e+e- Collisions at sqrt(s) ~189GeV
The OPAL collaboration, G. Abbiendo
A search for neutral Higgs bosons has been performed with the OPAL detector at LEP, using approximately 170 pb-1 of e+e- collision data collected at sqrt(s)~189GeV. Searches have b…