A. A. Pankov

Spin identification of the Randall-Sundrum resonance in lepton-pair production at the CERN LHC

The determination of the spin of the quantum states exchanged in the various nonstandard interactions is a relevant aspect in the identification of the corresponding scenarios. We discuss the identification reach at the CERN LHC on the spin-2 of the lowest-lying Randall-Sundrum (RS) resonance, predicted by gravity with one warped extra dimension, against spin-1 and spin-0 nonstandard exchanges with the same mass and producing the same number of events in the cross section. We focus on the angular distributions of leptons produced in the Drell-Yan process at the LHC; in particular, we use as a basic observable a normalized integrated angular asymmetry A{sub CE}. Our finding is that the 95% C.L. identification reach on the spin-2 of the RS resonance (equivalently, the exclusion reach on both the spin-1 and spin-0 hypotheses for the peak) is up to a resonance mass scale of the order of 1.0 or 1.6 TeV in the case of weak coupling between graviton excitations and SM particles (k/M{sub Pl}=0.01) and 2.4 or 3.2 TeV for a larger coupling constant (k/M{sub Pl}=0.1) for a time-integrated LHC luminosity of 10 or 100 fb{sup -1}, respectively. Also, some comments are given on the complementary roles of the angular analysismorexa0» and the eventual discovery of the predicted second graviton excitation in the identification of the RS scenario.«xa0less

Spin-analysis of s-channel diphoton resonances at the LHC

The high mass neutral quantum states envisaged by theories of physics beyond the standard model can, at the hadron colliders, reveal themselves through their decay into a pair of photons. Once such a peak in the diphoton invariant mass distribution is discovered, the determination of its spin through the distinctive photon angular distributions is needed in order to identify the associated nonstandard dynamics. We discuss here the discrimination of the spin-2 Randall-Sundrum graviton excitation against the hypothesis of a spin-0 exchange giving the same number of events under the peak, by means of the angular analysis applied to resonant diphoton events expected to be observed at the LHC. The spin-0 hypothesis is modeled by an effective interaction of a high mass gauge singlet scalar particle interacting with the standard model fields. The basic observable of our analysis is the symmetrically integrated angular asymmetry A CE , calculated for both graviton and scalar s-channel exchanges to next-to-leading order in QCD.

Precise determination of Z-Z' mixing at the CERN LHC

We discuss the expected sensitivity to

Distinguishing new physics scenarios at a linear collider with polarized beams

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Theoretical speculations on the TRISTAN results at s⩽60GeV

boson effects in the

Role of beam polarization in the determination of WW gamma and WWZ couplings from e+e--->W+W-

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Spin Identification of the Randall-Sundrum Graviton at the LHC

boson pair production process at the Large Hadron Collider (LHC). The results of a model-dependent analysis of

Sneutrino identification in lepton pair production at ILC with polarized beams

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Direct manifestation of the additional isoscalar bosons in the process e+e− → ff̄ at LEP

boson effects are presented as constraints on the

Spin identification of heavy nonstandard bosons in dilepton and diphoton events at the LHC

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