117156652
Properties of Quark and Gluon Jets — a LEP Mini Review
Recent results on the structure of and differences between quark and gluon jets from the four LEP experiments are reviewed.
65296691
ATLAS computing: Technical design report.
120991534
B-physics in the p-p collisions at the LHC
The LHC provides an excellent opportunity for B-physics studies, providing both high statistics and a wide range of kinematic conditions. This paper summarises the prospects for the ATLAS, CMS and LHCb experiments, with an emphasis on the QCD aspects. The rather different programme of the heavy-ions experiment ALICE is not addressed. The experiments will probe both the production and decay of B-hadrons. The various trigger strategies are presented, after which the production measurements are considersed and are shown to provide stringent test of QCD, as well as providing vital information of the backgrounds to searches. After this, the studies of B-decays are presented. The measurements of CP-violation are shown to have a good potential for discovering signatures of new physics. B s mixing will also open a window on new physics, and Δ| Gamma s will be measurable. Finally, the prospects for rare deacys are considered, especially for the decays to muons.
62239385
The ATLAS computing model
The ATLAS Computing Model was constructed after early tests and was captured in the ATLAS Computing TDR in June 2005. Since then, the grid tools and services have evolved and their performance is starting to be understood through large-scale exercises. As real data taking becomes immanent, the computing model continues to evolve, with robustness and reliability being the watchwords for the early deployment. Particular areas of active development are the data placement and data access, and the interaction between the TAGs, the datasets and the Distributed Data Management issues. The earlier high-level policies and models are now being refined into lower level instantiations.
123293754
Production of charmed hadrons in neutrino proton and antineutrino proton charged current interactions
AbstractUsind data from avp and
$$\bar v$$
p experiment with BEBC at CERN, the rates for inclusive production ofD*+,Λc+ andD0 invp scattering and ofD*− in
$$\bar v$$
p scattering are measured. Some examples of the exclusive production ofD*+,Λc+ and∑c++ are given. The cross section for the reactionvp→μ−c++ is estimated.
121691932
W mass measurements at LEP and the Tevatron
The prospects for precise tests of the standard model by measuring the mass of the W boson at LEP II and the Tevatron are considered. The limiting systematic effects are discussed.
17352400
The criteria for a solution of the field equations to be a classical limit of a quantum cosmology
If the gravitational field is quantized, then a solution of Einstein's field equations is a valid cosmological model only if it corresponds to a classical limit of a quantum cosmology. To determine which solutions are valid requires looking at quantum cosmology in a particular way. Because we infer the geometry by measurements on matter, we can represent the amplitude for any measurement in terms of the amplitude for the matter fields, allowing us to integrate out the gravitational degrees of freedom. Combining that result with a path-integral representation for quantum cosmology leads to an integration over 4-geometries. Even when a semiclassical approximation for the propagator is valid, the amplitude for any measurement includes an integral over the gravitational degrees of freedom. The conditions for a solution of the field equations to be a classical limit of a quantum cosmology are: (1) The effect of the classical action dominates the integration, (2) the action is stationary with respect to variation of the gravitational degrees of freedom, and (3) only one saddlepoint contributes significantly to each integration.
17515691
The classical action for a Bianchi VI_h model
An estimate for the classical action for a Bianchi VI_h homogeneous spatially closed cosmology is presented as a function of b, a parameter of the model that is proportional to the relative rotation of the average inertial frame and the bulk of matter in the universe. It is assumed (through the equation of state) that a relativistic early universe is followed by a matter-dominated late universe. The action is used in a saddlepoint approximation to a semiclassical estimate for the wave function in quantum cosmology to explain why our inertial frame seems not to rotate relative to the stars. The saddlepoint is at b=0, as would be expected. Application of the saddlepoint approximation leads to the result that only those classical geometries whose action differs from the saddlepoint value for the action by an amount less than Planck's constant contribute significantly to the integration to give the present value of the wave function. Using estimates for our universe implies that only those classical geometries for which the present relative rotation rate of inertial frames and matter are less than about 10^(-130) radians per year contribute significantly to the integration. This is well below the limit set by experiment. The result depends on the ratio of the Hubble distance to the Planck length, but does not depend on the details of the theory of quantum gravity.