Beam-induced backgrounds in the CLIC 3 TeV CM energy interaction region

Luminosity spectrum and accelerator background levels strongly influence the experimental conditions and have an important impact on detector design. The expected rates of the main beam-beam products at CLIC 3 TeV CM energy, taking into account for machine imperfections, are computed. Among the other machine-induced background the photon fans from the Incoherent Synchrotron Radiation (ISR) photons emitted in the final doublet are evaluated.Comment: Proceedings of LCWS1

Computational Fluid Dynamics Applied to Transport Systems in Trees

Our ecosystem is dependent upon the ability of photosynthetic plants to convert solar energy into a form of energy useable to biological organisms. Even so, much remains to become understood about how plants function. With such expansive bodies,how do trees cyclewaterand nutrients throughouttheir bodies

Searching for Stars in Compact High-Velocity Clouds. II

We address the hypothesis that High Velocity Clouds correspond to the "missing" dwarf galaxies of the Local Group predicted by cosmological simulations. To this end, we present optical and near-infrared photometry of five additional High Velocity Clouds, one of which produces Lyman series absorption on the sight line towards the Quasar Ton S210, with sufficient resolution and sensitivity to enable the detection of an associated stellar content. We do not detect significant stellar populations intrinsic to any of the five clouds. In combination with the results from our paper I, which had yielded non detections of stellar content in another five cases, we find that there is a 50% chance of getting a null result in ten trials if fewer than 7% of all High Velocity Clouds contain stars. We conclude that the population of High Velocity Clouds is an unlikely repository for the "missing" dwarfs of the Local Group.Comment: 6 pages, 3 figures. submitted to MNRA

Experimental determination of the effects of moisture on composite-to-composite adhesive joints

The primary mode of moisture ingress into bonded composite joints is determined using a nuclear probe for deuterium (NPD) to measure the localized D2O content along the length of the adhesive (FM-300 and EA-9601) and through the thickness of bonded composite speciments. Calculated diffusivities and NPD measured equilibrium moisture contents are used to predict the moisture profiles along the length of the adhesives as a function of exposure time, temperature, and relative humidity. These results are compared with the observed moisture profiles to evaluate the extent of enhanced edge diffusion. The FM-300 adhesive exhibits good agreement between measured and predicted profiles at 49 C, 70% and 90% RH, and 77 C, 70% RH. At 77 C, 90% RH, the measured moisture content near the adhesive edge is substantially larger than the predicted level. The EA-9601 adhesive also shows good agreement at 49 C, 70% and 90% RH, but at 77 C, the concentration of D20 near the edges is enhanced at each humidity level. The effect of moisture content on the bond shear strength at room temperature and at elevated temperature is evaluated

Treatment approaches for dual diagnosis clients in England

Introduction - Dual diagnosis (DD, co-occurrence of substance use and mental health problems) prevalence data in England are limited to specific regions and reported rates vary widely. Reliable information on actual service provision for dual diagnosis clients has not been collated. Thus a national survey was carried out to estimate dual diagnosis prevalence in treatment populations and describe the service provision available for this client population in drug/alcohol (DAS) and mental health services (MHS). Design - A questionnaire was sent to managers of 706 DAS and 2374 MHS. Overall, 249 (39%) DAS and 493 (23%) MHS participated in the survey. Results - In both DAS and MHS, around 32% of clients were estimated to have dual diagnosis problems. However, fewer than 50% of services reported assessing clients for both problem areas. Regarding specific treatment approaches, most services (DAS: 88%, MHS: 87%) indicated working jointly with other agencies. Significantly fewer services used joint protocols (DAS: 55%, MHS: 48%) or shared care arrangements, including access to external drug/alcohol or mental health teams (DAS: 47%, MHS: 54%). Only 25% of DAS and 17% of MHS employed dual diagnosis specialists. Conclusions - Dual diagnosis clients constitute a substantial proportion of clients in both DAS and MHS in England. Despite recent policy initiatives, joint working approaches tend to remain unstructured

Digital Use and Internet Access in Fayetteville, Arkansas

A report on data gathered from a spring 2019 survey by the UA Center for Communication Research. The data will provide the City of Fayetteville with a baseline picture regarding residents’ current levels of internet access, their daily activities online, the importance of the internet to them, and the barriers they see to enhanced online access. Future study will consider the homework gap in homes with K-12 students as well as general internet access issues for residential multi-tenant environments. Data from this survey will inform the City of Fayetteville\u27s Digital Equity Plan

Searching for Stars in Compact High-Velocity Clouds. I First Results from VLT and 2MASS

We investigate the hypothesis that compact high-velocity clouds (CHVC) are the "missing" dwarf galaxies of the Local Group, by searching them for populations of resolved stars. To this end we conducted two distinct tests based on optical and near-infrared single-star photometry. The optical and the near-infrared experiments complement one another; the optical data help us to rule out distant populations but they are restricted to the central regions of the gas distributions, whereas the near-infrared photometry allows us to set limits on nearby populations spread over the typical cloud size. First, we discuss deep optical single-star photometry of five CHVCs in the V and I filters, obtained with the FORS instrument at the Very Large Telecope (VLT). We find that their optical colour-magnitude diagrams are indistinguishable from that of a population of Galactic stars, and attribute all of the resolved stars to Galactic foreground. We present simulations which address the question of how much of a "normal" dwarf-galaxy type population we might hide in the data. A Kolmogorov-Smirnov test allows us to set very stringent limits on the absence of a resolved stellar population in CHVCs. Second, we also culled near infrared single-star photometry in the J, H, and K_S bands for four of the CHVCs from the Two Micron All Sky Survey (2MASS). The infrared data do not reveal any stellar contents in the CHVCs which resembles that of nearby dwarf galaxies either, and are explained with Galactic foreground as well. We interpret our null detections to indicate that the five CHVCs investigated by us do not host an associated stellar content which is similar to that of the known dwarf galaxies of the Local Group. These CHVCs are very likely pure hydrogen clouds in which no star formation has taken place over cosmic time.Comment: 13 pages, 10 figures, accepted for publication by MNRA

Optimal Control for Generating Quantum Gates in Open Dissipative Systems

Optimal control methods for implementing quantum modules with least amount of relaxative loss are devised to give best approximations to unitary gates under relaxation. The potential gain by optimal control using relaxation parameters against time-optimal control is explored and exemplified in numerical and in algebraic terms: it is the method of choice to govern quantum systems within subspaces of weak relaxation whenever the drift Hamiltonian would otherwise drive the system through fast decaying modes. In a standard model system generalising decoherence-free subspaces to more realistic scenarios, openGRAPE-derived controls realise a CNOT with fidelities beyond 95% instead of at most 15% for a standard Trotter expansion. As additional benefit it requires control fields orders of magnitude lower than the bang-bang decouplings in the latter.Comment: largely expanded version, superseedes v1: 10 pages, 5 figure