Professor Brian Foster OBE, FRS

Abstract:

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, V-ud & V-us, V-cb & V-ub, top quark, muon anomalous magnetic moment, extra dimensions, particle detectors, cosmic background radiation, dark matter, cosmological parameters, and big bang cosmology.

Abstract:

Inclusive KS0KS0 production in ep collisions at the DESY ep collider HERA was studied with the ZEUS detector using an integrated luminosity of 0.5fb-1. Enhancements in the mass spectrum were observed and are attributed to the production of f2(1270)/a20(1320), f2′(1525) and f0(1710). Masses and widths were obtained using a fit which takes into account theoretical predictions based on SU(3) symmetry arguments, and are consistent with the Particle Data Group values. The f0(1710) state, which has a mass consistent with a glueball candidate, was observed with a statistical significance of 5 standard deviations. However, if this state is the same as that seen in γγ→KS0KS0, it is unlikely to be a pure glueball state. © 2008 The American Physical Society.

Abstract:

Deep inelastic scattering and its diffractive component, e p → e^′ γ^* p → e^′ X N, have been studied at HERA with the ZEUS detector using an integrated luminosity of 52.4 pb^-1. The MX method has been used to extract the diffractive contribution. A wide range in the centre-of-mass energy W (37-245 GeV), photon virtuality Q² (20-450 GeV²) and mass MX (0.28-35 GeV) is covered. The diffractive cross section for 2 < MX < 15 GeV rises strongly with W, the rise becoming steeper as Q² increases. The data are also presented in terms of the diffractive structure function, F2^{D (3)}, of the proton. For fixed Q² and fixed MX, xP F2^{D (3)} shows a strong rise as xP → 0, where xP is the fraction of the proton momentum carried by the pomeron. For Bjorken-x < 1 × 10^-3, xP F2^{D (3)} shows positive log Q² scaling violations, while for x ≥ 5 × 10^-3 negative scaling violations are observed. The diffractive structure function is compatible with being leading twist. The data show that Regge factorisation is broken. © 2008 Elsevier B.V. All rights reserved.

Abstract:

Jet cross sections were measured in charged-current deep inelastic e±p scattering at high boson virtualities Q2 with the ZEUS detector at HERA II using an integrated luminosity of 0.36fb-1. Differential cross sections are presented for inclusive-jet production as functions of Q2, Bjorken x and the jet transverse energy and pseudorapidity. The dijet invariant mass cross section is also presented. Observation of three- and four-jet events in charged-current e±p processes is reported for the first time. The predictions of next-to-leading-order (NLO) QCD calculations are compared to the measurements. The measured inclusive-jet cross sections are well described in shape and normalization by the NLO predictions. The data have the potential to constrain the u and d valence-quark distributions in the proton if included as input to global fits. © 2008 The American Physical Society.

Abstract:

The charged multiplicity distributions and the mean charged multiplicity have been investigated in inclusive neutral current deep inelastic ep scattering with the ZEUS detector at HERA, using an integrated luminosity of 38.6 pb-1. The measurements were performed in the current region of the Breit frame, as well as in the current fragmentation region of the hadronic centre-of-mass frame. The KNO-scaling properties of the data were investigated and the energy dependence was studied using different energy scales. The data are compared to results obtained in e+e- collisions and to previous DIS measurements as well as to leading-logarithm parton-shower Monte Carlo predictions. © SISSA 2007.