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On quantum corrections to spinning strings and Bethe equations
(2005)Physics Letters BRecently, it was demonstrated that oneloop energy shifts of spinning superstrings on AdS5 x S5 agree with certain Bethe equations for quantum strings at small effective coupling. However, the string result required artificial regularization by zetafunction. Here we show that this matching is indeed correct up to fourth order in effective coupling; beyond, we find new contributions at odd powers. We show that these are reproduced by ...Journal Article 
Measurement of the running of the electromagnetic coupling at large momentumtransfer at LEP
(2005)Physics Letters BThe evolution of the electromagnetic coupling, α, in the momentumtransfer range 1800 GeV2 < Q2 < 21600 GeV2 is studied with about 40 000 Bhabhascattering events collected with the L3 detector at LEP at centreofmass energies √s = 189209 GeV. The running of α is parametrised as: α(Q2) = α0/1  C Δα(Q2), where α ≡ α(Q2 = 0) is the finestructure constant and C = 1 corresponds to the evolution expected in QED. A fit to the differential ...Journal Article 
Fluctuations and energy shifts in the Bethe ansatz
(2005)Physics Letters BWe study fluctuations and finite size corrections for the ferromagnetic thermodynamic limit in the Bethe ansatz for the Heisenberg WWW 1/2 spin chain, which is the AdS/CFT dual of semiclassical spinning strings. For this system we derive the standard quantum mechanical formula which expresses the energy shift as a sum over fluctuation energies. As an example we apply our results to the simplest, onecut solution of this system and derive ...Journal Article 
Measurement of charm and beauty photoproduction at HERA using D*mu correlations
(2005)Physics Letters B ~ Physics letters. BA measurement of charm and beauty photoproduction at the electron proton collider HERA is presented based on the simultaneous detection of a D*± meson and a muon. The correlation between the D* meson and the muon serves to separate the charm and beauty contributions and the analysis provides comparable sensitivity to both. The total and differential experimental cross sections are compared to LO and NLO QCD calculations. The measured charm ...Journal Article 
Spatially highly resolved study of AFM scanning tipquantum dot local interaction
(2005)New Journal of PhysicsScanninggate imaging of semiconductor quantum dots (QDs) promises access to probability distributions of quantum states. It could therefore be a novel tool for designing and optimizing tailored quantum states in such systems. A detailed study of a lithographically defined semiconductor QD in the Coulombblockade regime is presented, making use of the scanninggate technique at a base temperature of 300 mK. The method allows a onebyone ...Journal Article 
Neutralcurrent fourfermion production in e+e interactions at LEP
(2005)Physics Letters BNeutralcurrent fourfermion production, e+e →ff̄f′f̄′, is studied in 0.7 fb 1 of data collected with the L3 detector at LEP at centreofmass energies s=183209 GeV. Four final states are considered: qq̄νν̄ , qq̄ℓ+ℓ, ℓ+ℓℓ′+ℓ′ and ℓ+ℓνν̄, where ℓ denotes either an electron or a muon. Their cross sections are measured and found to agree with the Standard Model predictions. In addition, the e+e→Zγ *→ff̄f′f̄′ process is studied and ...Journal Article 
Search for light gravitinos in events with photons and missing transverse momentum at HERA
(2005)Physics Letters BJournal Article 
Gluon–gluon antenna functions from Higgs boson decay
(2005)Physics Letters BAntenna functions describe the infrared singular behaviour of colourordered QCD matrix elements due to the emission of unresolved partons inside an antenna formed by two hard partons. In this Letter, we show that antenna functions for hard gluon–gluon pairs can be systematically derived from the effective Lagrangian describing Higgs boson decay into gluons, and compute the infrared structure of the colourordered Higgs boson decay matrix ...Journal Article 
Quark–gluon antenna functions from neutralino decay
(2005)Physics Letters BThe computation of exclusive QCD jet observables at higher orders requires a method for the subtraction of infrared singular configurations arising from multiple radiation of real partons. One commonly used method at nexttoleading order (NLO) is based on the antenna factorization of colourordered matrix elements, and uses antenna functions to subtract the real radiation singularities. Up to now, NLO antenna functions could be derived ...Journal Article 
Databases of surface wave dispersion
(2005)Annals of GeophysicsObservations of seismic surface waves provide the most important constraint on the elastic properties of the Earths lithosphere and upper mantle. Two databases of fundamental mode surface wave dispersion were recently compiled and published by groups at Harvard (Ekström et al., 1997) and Utrecht/Oxford (Trampert and Woodhouse, 1995, 2001), and later employed in 3d global tomographic studies. Although based on similar sets of seismic ...Journal Article