LHCb Upgrade Plans

The LHCb experiment will operate for about five years at a luminosity of 2x10^32 cm^-2 s^-1 and plans are to accumulate a data sample of ~10 fb^-1. Here we present the physics programme and detector design for a future high luminosity phase of the LHCb experiment. An upgraded LHCb experiment would operate at ten times the design luminosity, i.e. at ~2x10^33 cm^-2 s^-1 and aims to collect a data sample of ~100 fb^-1 over five years. This programme would allow the probe of new physics at an unprecedented level. Key measurements include the B^0_s mixing phase phi_s in B^0_s -> J/\psi phi and B^0_s -> phi phi decays with a significant sensitivity to the small Standard Model prediction and a very precise measurement of the CKM angle gamma in tree diagram decays. Initial studies of the modified LHCb trigger and detectors are presented. The upgraded LHCb experiment can run with or without an LHC luminosity upgrade.Comment: 6 pages, 2 figures, to appear in the proceedings of International Conference on B-Physics at Hadron Machines (Beauty 2006), Oxford, England, 25-29 Sep 200

A unified approach for the identification of SISO/MIMO Wiener and Hammerstein systems

Hammerstein and Wiener models are nonlinear representations of systems composed by the coupling of a static nonlinearity N and a linear system L in the form N-L and L-N respectively. These models can represent real processes which made them popular in the last decades. The problem of identifying the static nonlinearity and linear system is not a trivial task, and has attracted a lot of research interest. It has been studied in the available literature either for Hammerstein or Wiener systems, and either in a discrete-time or continuous-time setting. The objective of this paper is to present a uni ed framework for the identification of these systems that is valid for SISO and MIMO systems, discrete and continuous-time setting, and with the only a priori knowledge that the system is either Wiener or Hammerstein.Preprin

Influence of Mortar Rheology on Aggregate Settlement

The influence of the rheology of fresh concrete on the settlement of aggregate is examined. Fresh concrete exhibits a yield stress that, under certain conditions, prevents the settlement of coarse aggregate, although its density is larger than that of the suspending mortar. Calculations, based on estimates of the yield stress obtained from slump tests, predict that aggregate normally used in concrete should not sink. To test this prediction, the settlement of a stone in fresh mortar is monitored. The stone does not sink in the undisturbed mortar (which has a high yield stress), but sinks when the mortar is vibrated, presumably due to a large reduction in its yield stress. This implies that during placement of concrete, the aggregate settles only while the concrete is being vibrated. A unique experimental method for measuring aggregate settlement is also introduced and demonstrated

Partitioning of Poly(amidoamine) Dendrimers between n-Octanol and Water

Dendritic nanomaterials are emerging as key building blocks for a variety of nanoscale materials and technologies. Poly(amidoamine) (PAMAM) dendrimers were the first class of dendritic nanomaterials to be commercialized. Despite numerous investigations, the environmental fate, transport, and toxicity of PAMAM dendrimers is still not well understood. As a first step toward the characterization of the environmental behavior of dendrimers in aquatic systems, we measured the octanol−water partition coefficients (logK_(ow)) of a homologous series of PAMAM dendrimers as a function of dendrimer generation (size), terminal group and core chemistry. We find that the logKow of PAMAM dendrimers depend primarily on their size and terminal group chemistry. For G1-G5 PAMAM dendrimers with terminal NH_2 groups, the negative values of their logK_(ow) indicate that they prefer to remain in the water phase. Conversely, the formation of stable emulsions at the octanol−water (O/W) interface in the presence of G6-NH_2 and G8-NH_2 PAMAM dendrimers suggest they prefer to partition at the O/W interface. In all cases, published studies of the cytotoxicity of Gx-NH_2 PAMAM dendrimers show they strongly interact with the lipid bilayers of cells. These results suggest that the logKow of a PAMAM dendrimer may not be a good predictor of its affinity with natural organic media such as the lipid bilayers of cell membranes

Equivariant estimation of a mean vector μ of N(μ, Σ) with μ′Σ−1μ = 1 or Σ−12μ = c or Σ = σ2μ′μl

AbstractThis paper considers the problems of estimating a mean vector μ under constraint μ′Σ−1μ = 1 or Σ−12μ = c and derives the best equivariant estimators under the loss (a − μ)′ Σ−1(a − μ), which dominate the MLE's uniformly. The results are regarded as multivariate extensions of those with known coefficient of variation in a univariate case. As a particular case for μ′Σ−1μ = c, the case Σ = σ2μ′μI is also treated

Boundary contributions to the hypervirial theorem

It is shown that, under certain boundary conditions, the virial theorem has to be modified. We analyze the origin of the extra term and compute it for particular examples. The Coulomb and harmonic oscillator with the point interaction have been studied in light of this generalization of the virial theorem