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Collider aspects of flavor physics at high Q
(2008)The European Physical Journal CThis chapter of the “Flavor in the era of LHC” workshop report discusses flavor-related issues in the production and decays of heavy states at the LHC at high momentum transfer Q, both from the experimental and the theoretical perspective. We review top quark physics, and discuss the flavor aspects of several extensions of the standard model, such as supersymmetry, little Higgs models or models with extra dimensions. This includes discovery ...Journal Article -
A precise measurement of the muon neutrino–nucleon inclusive charged current cross section off an isoscalar target in the energy range 2.5 < Eν < 40 GeV by NOMAD
(2008)Physics Letters BWe present a measurement of the muon neutrino-nucleon inclusive charged current cross section, off an isoscalar target, in the neutrino energy range 2.5 ≤ E ν ≤ 40 GeV. The significance of this measurement is its precision, ±4% in 2.5 ≤ E ν ≤ 10 GeV, and ±2.6% in 10 ≤ E ν ≤ 40 GeV regions, where significant uncertainties in previous experiments still exist, and its importance to the current and proposed long baseline neutrino oscillation ...Journal Article -
B , D and K decays
(2008)The European Physical Journal CThe present report documents the results of Working Group 2: B, D and K decays, of the workshop on Flavor in the Era of the LHC, held at CERN from November 2005 through March 2007. With the advent of the LHC, we will be able to probe New Physics (NP) up to energy scales almost one order of magnitude larger than it has been possible with present accelerator facilities. While direct detection of new particles will be the main avenue to ...Journal Article -
Study of b-quark mass effects in multijet topologies with the DELPHI detector at LEP
(2008)The European Physical Journal CThe effect of the heavy b-quark mass on the two, three and four-jet rates is studied using LEP data collected by the DELPHI experiment at the Z peak in 1994 and 1995. The rates of b-quark jets and light quark jets (ℓ=uds) in events with n=2, 3, and 4 jets, together with the ratio of two and four-jet rates of b-quarks with respect to light-quarks, Rn bℓ, have been measured with a double-tag technique using the CAMBRIDGE jet-clustering ...Journal Article -
Probing quantum gravity using photons from a flare of the active galactic nucleus Markarian 501 observed by the MAGIC telescope
(2008)Physics Letters BWe analyze the timing of photons observed by the MAGIC telescope during a flare of the active galactic nucleus Mkn 501 for a possible correlation with energy, as suggested by some models of quantum gravity (QG), which predict a vacuum refractive index ≃ 1 + (E / MQGn)n, n = 1, 2. Parametrizing the delay between γ-rays of different energies as Δ t = ± τl E or Δ t = ± τq E2, we find τl = (0.030 ± 0.012) s / GeV at the 2.5-σ level, and τq = ...Journal Article -
Flavor physics of leptons and dipole moments
(2008)The European Physical Journal CThis chapter of the report of the “Flavor in the era of the LHC” Workshop discusses the theoretical, phenomenological and experimental issues related to flavor phenomena in the charged lepton sector and in flavor conserving CP-violating processes. We review the current experimental limits and the main theoretical models for the flavor structure of fundamental particles. We analyze the phenomenological consequences of the available data, ...Journal Article -
Measurement of the Mass and Width of the W Boson in e+ e- Collisions at s**(1/2) = 161-GeV - 209-GeV
(2008)The European Physical Journal CA measurement of the W boson mass and width has been performed by the DELPHI collaboration using the data collected during the full LEP2 programme (1996–2000). The data sample has an integrated luminosity of 660 pb-1 and was collected over a range of centre-of-mass energies from 161 to 209 GeV. Results are obtained by applying the method of direct reconstruction of the mass of the W from its decay products in both the W+W-→ℓν̄ℓqq̄’ and ...Journal Article -
Study of W Boson Polarisations and Triple Gauge Boson Couplings in the Reaction e+e- -> W+W- at LEP 2
(2008)The European Physical Journal CA determination of the single W spin density matrix (SDM) elements in the reaction e+e-→W+W-→lνqq̄(l=e/μ) is reported at centre-of-mass energies between 189 and 209 GeV. The data sample used corresponds to an integrated luminosity of 520 pb-1 taken by DELPHI between 1998 and 2000. The single W SDM elements, ρττ’ W± (τ,τ’=± 1 or 0), are determined as a function of the W- production angle with respect to the e- beam direction and are obtained ...Journal Article -
Study of hadronic event shape in flavour tagged events in e+e- annihilation at ⟨√s⟩ = 197 GeV
(2008)PMC Physics. AResults are presented from a study of the structure of hadronic events in high-energy e+e- interactions detected by the L3 detector at LEP. Various event shape distributions and their moments are measured at several energy points at and above the Z-boson mass. The event flavour is tagged by using the decay characteristics of b-hadrons. Measurements of distributions of event shape variables for all hadronic events, for light (u, d, s, c) ...Journal Article -