Review of Final LEP Results or A Tribute to LEP

After a comment on the performance of LEP some highlights of the LEP1 and LEP2 physics programmes are reviewed. The talk concentrates on the precision measurements at the Z resonance, two fermion production above the Z, W+W- production, ZZ production, indirect limits on the Higgs mass, LEP contributions to the exploration of the CKM matrix, and on the LEP measurements of alpha_s.Comment: Proceedings of the XX International Symposium on Lepton and Photon Interactions at High Energies Rome, Italy, July 200

The Modern FPGA as Discriminator, TDC and ADC

Recent generations of Field Programmable Gate Arrays (FPGAs) have become indispensible tools for complex state machine control and signal processing, and now routinely incorporate CPU cores to allow execution of user software code. At the same time, their exceptional performance permits low-power implementation of functionality previously the exclusive domain of dedicated analog electronics. Specific examples presented here use FPGAs as discriminator, time-to-digital (TDC) and analog-to-digital converter (ADC). All three cases are examples of instrumentation for current or future astroparticle experiments.Comment: 7 pages, v3 minor JINST editorial correction

Triggering on hard probes in heavy ion collisions with CMS

We present a study of the CMS trigger system in heavy-ion collisions. Concentrating on two physics channels, dimuons from decays of quarkonia and single jets, we evaluate a possible trigger strategy for Pb+Pb running that relies on event selection solely in the High-Level Trigger (HLT). The study is based on measurements of the timing performance of the offline algorithms and event-size distributions using full simulations. Using a trigger simulation chain, we compare the physics reach for the jet and dimuon channels using online selection in the HLT to minimum bias running. The results demonstrate the crucial role the HLT will play for CMS heavy-ion physics.Comment: 4 pages, 4 fugures, contribution to QM'06 conferenc

Particle Flow Calorimetry at the ILC

One of the most important requirements for a detector at the ILC is good jet energy resolution. It is widely believed that the particle flow approach to calorimetry is the key to achieving the goal of 0.3/sqrt(E[GeV]). This paper describes the current performance of the PandoraPFA particle flow algorithm. For 45 GeV jets in the Tesla TDR detector concept, the ILC jet energy resolution goal is reached. At higher energies the jet energy resolution becomes worse and can be described by the empirical expression: sigma_E/E ~ 0.265/sqrt(E[GeV]) + 1.2x10^{-4}E[GeV].Comment: 5 pages, 2 .eps figures, to appear in Proc. LCWS06, Bangalore, March 200

Remarks Concerning the Study of Four-Jet Events from Hadronic Decays of the Z0

The angular correlations of four-jet events from hadronic decays of the Z0 have been studied in the past mainly to extract from them the fundamental constants of quantum chromodynamics called colour factors. Previous studies have used all the available phase-space in order to maximize statistics. In this note we want to point out the possibility that significant differences between experiment and theory in restricted regions of phase-space might have escaped detection. Such differences could be a harbinger of the existence of new particles. Some preliminary results are presented.Comment: 9 pages, 3 figure

A QCD analysis of diffractive deep-inelastic scattering data

We perform a novel type of analysis of diffractive deep-inelastic scattering data, in which the input parton distributions of the Pomeron are parameterised using the perturbative QCD expressions. In particular, we treat individually the components of the Pomeron of different size. We are able to describe simultaneously both the recent ZEUS and H1 diffractive data. In addition to the usual two-gluon model for the perturbative Pomeron, we allow for the possibility that it may be made from two sea quarks.Comment: 13 pages, 5 figures. Version published in Eur. Phys. J.

Nucleon form factors, B-meson factories and the radiative return

The feasibility of a measurement of the electric and magnetic nucleon form factors at $B$-meson factories through the radiative return is studied. Angular distributions allow a separation of the contributions from the two form factors. The distributions are presented for the laboratory and the hadronic rest frame, and the advantages of different coordinate systems are investigated. It is demonstrated that $Q^2$ values up to 8 or even 9 GeV$^2$ are within reach. The Monte Carlo event generator PHOKHARA is extended to nucleon final states, and results are presented which include Next-to-Leading Order radiative corrections from initial-state radiation. The impact of angular cuts on rates and distributions is investigated and the relative importance of radiative corrections is analysed.Comment: 9 pages, 11 figures. Final version to appear in Eur. Phys. J.

Unintegrated parton distributions and inclusive jet production at HERA

We describe how unintegrated parton distributions can be calculated from conventional integrated distributions. We extend and improve the 'last-step' evolution approach, and explain why doubly-unintegrated parton distributions are necessary. We generalise k_t-factorisation to (z,k_t)-factorisation. We apply the formalism to inclusive jet production in deep-inelastic scattering, mainly at leading-order, but we also study the extension to next-to-leading order. We compare the predictions with recent HERA data.Comment: 32 pages, 11 figures. Version to appear in Eur. Phys. J.