This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2778 new measurements from 645 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. Among the 108 reviews are many that are new or heavily revised including those on CKM quark-mixing matrix, Vud & Vus , Vcb & Vub , top quark, muon anomalous magnetic moment, extra dimensions, particle detectors, cosmic background radiation, dark matter, cosmological parameters, and big bang cosmology. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.lbl.gov
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We calculate the O(α 3 s ) heavy flavor contributions to the Wilson coefficients of the structure function F 2 (x, Q 2 ) and the massive operator matrix elements (OMEs) for the twist-2 operators of unpolarized deeply inelastic scattering in the region Q 2 ≫ m 2 . The massive Wilson coefficients are obtained as convolutions of massive OMEs and the known light flavor Wilson coefficients. We also compute the massive OMEs which are needed to evaluate heavy flavor parton distributions in the variable flavor number scheme (VFNS) to 3-loop order. All contributions to the Wilson coefficients and operator matrix elements but the genuine constant terms at O(α 3 s ) of the OMEs are derived in terms of quantities, which are known for general values in the Mellin variable N . For the operator matrix elements A /µ 2 , m 2 i /µ 2 ) this approximation is only valid for Q 2 /m 2 > ∼ 800, [29]. The 3-loop corrections were calculated in Ref. [30].3 massive operator matrix elements A jk contributing to the heavy flavor Wilson coefficients for the structure function F 2 (x, Q 2 ) in the region Q 2 /m 2 > ∼ 10 to 3-loop order for fixed moments of the Mellin variable N. In case of the flavor non-singlet (NS) contributions, we also present the odd moments of the −-projection. We further calculate the operator matrix elements, which are required to define heavy quark densities in the VFNS [31]. Due to renormalization, higher order contributions in ε to corrections of lower order in a s , cf. [29,[31][32][33][34][35], and other renormalization terms, such as the anomalous dimensions and the expansion coefficients of the QCD β-function and mass anomalous dimensions, contribute. For these reasons, the present calculation yields also the moments of the complete 2-loop anomalous dimensions and the terms ∝ T F of the 3-loop anomalous dimensions γ ij (N). In the pure singlet (PS) case, γ +,PS qq (N), and for γ qg (N), these are the complete anomalous dimensions given in [18,19], to which we agree. Since the present calculation is completely independent by method, formalism, and codes, it provides a check on the previous results. Except for the constant part of the unrenormalized heavy flavor operator matrix elements, we obtain the heavy quark Wilson coefficients in the asymptotic region for all values of the Mellin variable N. The analytic continuation of these expressions to complex values of N can be performed with the help of the representations in [36] and those given for the anomalous dimensions and massless Wilson coefficients in [18,19,26].The paper is organized as follows. In Section 2, a brief outline of the basic formalism is given. The renormalization of the different massive operator matrix elements is described in Section 3. In Section 4, we present details on the unrenormalized and renormalized operator matrix elements. Technical details of the calculation and the main results are discussed in Section 5. Depending on the CPU time and storage size required, the moments up to N = 10, 12, and 14 of the different operator matrix eleme...
We compute the total top-quark pair production cross section at the Tevatron and LHC based on approximate NNLO results, and on the summation of threshold logarithms and Coulomb enhancements to all orders with next-to-next-to-leading logarithmic (NNLL) accuracy, including bound-state effects. We find \sigma_{t\bar t} = 7.22^{+0.31+0.71}_{-0.47-0.55} pb at Tevatron and \sigma_{t\bar t} = 162.6^{+7.4+15.4}_{-7.6-14.7} pb at LHC with 7 TeV c.o.m. energy, for m_t=173.3 GeV. The implementation of joint soft and Coulomb resummation, its ambiguities, and the present theoretical uncertainty are discussed in detail. We further obtain new approximate results at N3LO.Comment: 55 pages, LaTeX, 13 figure
We determine the parton distribution functions (PDFs) in a next-to-next-to-leading order (NNLO) QCDanalysis of the inclusive neutral-current deep-inelastic-scattering (DIS) world data combined with the neutrino-nucleon DIS di-muon data and the fixed-target Drell-Yan data. The PDF-evolution is performed in the N f = 3 fixed-flavor scheme and supplementary sets of PDFs in the 4-and 5-flavor schemes are derived from the results in the 3-flavor scheme using matching conditions. The charm-quark DIS contribution is calculated in a general-mass variable-flavor-number (GMVFN) scheme interpolating between the zeromass 4-flavor scheme at asymptotically large values of momentum transfer Q 2 and the 3-flavor scheme at the value of Q 2 = m 2 c in a prescription of Buza-Matiounine-Smith-van Neerven (BMSN). The results in the GMVFN scheme are compared with those of the fixed-flavor scheme and other prescriptions used in global fits of PDFs. The strong coupling constant is measured at an accuracy of ≈ 1.5%. We obtain at NNLO α s (M 2 Z ) = 0.1135 ± 0.0014 in the fixed-flavor scheme and α s (M 2 Z ) = 0.1129 ± 0.0014 applying the BMSN prescription. The implications for important standard candle and hard scattering processes at hadron colliders are illustrated. Predictions for cross sections of W ± -and Z-boson, the top-quark pair-and Higgs-boson production at the Tevatron and the LHC based on the 5-flavor PDFs of the present analysis are provided.1
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