The λΛ\lambda\Lambda interaction and the reaction Ξ−+d→n+Λ+Λ\Xi^- + d \to n + \Lambda + \Lambda

The $\Lambda\Lambda$ interaction resulting from the SU(3) rotation of the S-wave component of the Nijmegen OBE potential $D$ is used to calculate the binding energy of $^{ 6}_{\Lambda\Lambda}$He as a $\Lambda\Lambda\alpha$ three-body system, and the neutron differential energy spectrum for the reaction $\Xi^- + d \to n + \Lambda + \Lambda$.Comment: 5 pages and 9 eps file

Obtaining a class of Type O pure radiation metrics with a cosmological constant, using invariant operators

Using the generalised invariant formalism we derive a class of conformally flat spacetimes whose Ricci tensor has a pure radiation and a Ricci scalar component. The method used is a development of the methods used earlier for pure radiation spacetimes of Petrov types O and N respectively. In this paper we demonstrate how to handle, in the generalised invariant formalism, spacetimes with isotropy freedom and rich Killing vector structure. Once the spacetimes have been constructed, it is straightforward to deduce their Karlhede classification: the Karlhede algorithm terminates at the fourth derivative order, and the spacetimes all have one degree of null isotropy and three, four or five Killing vectors.Comment: 29 page

Invariant classification and the generalised invariant formalism: conformally flat pure radiation metrics, with zero cosmological constant

Metrics obtained by integrating within the generalised invariant formalism are structured around their intrinsic coordinates, and this considerably simplifies their invariant classification and symmetry analysis. We illustrate this by presenting a simple and transparent complete invariant classification of the conformally flat pure radiation metrics (except plane waves) in such intrinsic coordinates; in particular we confirm that the three apparently non-redundant functions of one variable are genuinely non-redundant, and easily identify the subclasses which admit a Killing and/or a homothetic Killing vector. Most of our results agree with the earlier classification carried out by Skea in the different Koutras-McIntosh coordinates, which required much more involved calculations; but there are some subtle differences. Therefore, we also rework the classification in the Koutras-McIntosh coordinates, and by paying attention to some of the subtleties involving arbitrary functions, we are able to obtain complete agreement with the results obtained in intrinsic coordinates. In particular, we have corrected and completed statements and results by Edgar and Vickers, and by Skea, about the orders of Cartan invariants at which particular information becomes available.Comment: Extended version of GRG publication, with some typos etc correcte

Changes in orographic precipitation patterns caused by a shift from snow to rain

Climate warming will likely cause a shift from snow to rain in midlatitude mountains. Because rain falls faster than snow, it is not advected as far by prevailing winds before reaching the ground. A shift in precipitation phase thus may alter precipitation patterns. Using the Weather Research and Forecasting (WRF) regional climate model at 27-9-3 km resolutions over the California Sierra Nevada, we conducted an idealized experiment consisting of a present climate control run and two additional simulations in which (a) fall speed for snow is similar to rain and (b) all precipitation is constrained to fall as liquid. Rather than simulating future climates directly, these perturbation experiments allow us to test the potential impacts of changing precipitation phase in isolation from other factors such as variable large-scale atmospheric circulation. Relative to the control, both perturbations result in a rain shadow deepened by ̃30-60%, with increased focusing of precipitation on the western Sierra Nevada slopes best resolved at ≤9 km resolutions. Our results suggest that altered precipitation phase associated with climate change will likely affect spatial distributions of water resources, floods, and landslides in the Sierra Nevada and similar midlatitude mountain ranges. Citation: Pavelsky, T. M., S. Sobolowski, S. B. Kapnick, and J. B. Barnes (2012), Changes in orographic precipitation patterns caused by a shift from snow to rain, Geophys. Res. Lett., 39, L18706,

An observation of spin-valve effects in a semiconductor field effect transistor: a novel spintronic device

We present the first spintronic semiconductor field effect transistor. The injector and collector contacts of this device were made from magnetic permalloy thin films with different coercive fields so that they could be magnetized either parallel or antiparallel to each other in different applied magnetic fields. The conducting medium was a two dimensional electron gas (2DEG) formed in an AlSb/InAs quantum well. Data from this device suggest that its resistance is controlled by two different types of spin-valve effect: the first occurring at the ferromagnet-2DEG interfaces; and the second occuring in direct propagation between contacts.Comment: 4 pages, 2 figure

A two decade dementia incidence comparison from the Cognitive Function and Ageing Studies I and II.

Dramatic global increases in future numbers of people with dementia have been predicted. No multicentre population-based study powered to detect changes over time has reported dementia incidence. MRC Cognitive Function and Ageing Study (CFAS) undertook baseline interviews in populations aged 65+ years in England and Wales (1989-1994). Three areas (CFAS I) were selected for new sampling two decades later (2008-2011) with same geographical boundaries, sampling and approach methods (CFAS II). At 2 years CFAS I interviewed 5,156 (76% response) with 5,288 interviewed in CFAS II (74% response). Here we report a 20% drop in incidence (95% CI: 0-40%), driven by a reduction in men across all ages above 65. In the UK we estimate 209,600 new dementia cases per year. This study was uniquely designed to test for differences across geography and time. A reduction of age-specific incidence means that the numbers of people estimated to develop dementia in any year has remained relatively stable.CFAS II has been supported by the UK Medical Research Council (Research Grant: G06010220) and received additional support from the National Institute for Health Research (NIHR), comprehensive clinical research networks in West Anglia, Nottingham City and Nottinghamshire County NHS Primary Care trusts and the dementias and neurodegenerative disease research Network (DeNDRoN) in Newcastle. MRC CFAS I was funded by the MRC (Research Grant: G9901400) and the National Health Service (NHS). F.E.M. is supported by the MRC (Research Grant: U105292687). This research was done within the UK National Institute of Health Research collaboration for leadership in applied health research and care for Cambridgeshire and Peterborough (CLAHRC EoE), the Biomedical Research Centre infrastructures at Cambridge and Newcastle upon Tyne. We thank the participants, their families, the general practitioners and their staff, the primary care trusts and CCGs for their cooperation and support. We thank the CFAS II fieldwork interviewers at Cambridge, Nottingham and Newcastle for their valuable contribution. Funding was given by UK Medical Research Council.This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/ncomms1139

High-rate low-temperature dc pulsed magnetron sputtering of photocatalytic TiO2films: the effect of repetition frequency

The article reports on low-temperature high-rate sputtering of hydrophilic transparent TiO2thin films using dc dual magnetron (DM) sputtering in Ar + O2mixture on unheated glass substrates. The DM was operated in a bipolar asymmetric mode and was equipped with Ti(99.5) targets of 50 mm in diameter. The substrate surface temperature Tsurfmeasured by a thermostrip was less than 180 °C for all experiments. The effect of the repetition frequency frwas investigated in detail. It was found that the increase of frfrom 100 to 350 kHz leads to (a) an improvement of the efficiency of the deposition process that results in a significant increase of the deposition rate aDof sputtered TiO2films and (b) a decrease of peak pulse voltage and sustaining of the magnetron discharge at higher target power densities. It was demonstrated that several hundreds nm thick hydrophilic TiO2films can be sputtered on unheated glass substrates at aD = 80 nm/min, Tsurf < 180 °C when high value of fr = 350 kHz was used. Properties of a thin hydrophilic TiO2film deposited on a polycarbonate substrate are given

Detector Description and Performance for the First Coincidence Observations between LIGO and GEO

For 17 days in August and September 2002, the LIGO and GEO interferometer gravitational wave detectors were operated in coincidence to produce their first data for scientific analysis. Although the detectors were still far from their design sensitivity levels, the data can be used to place better upper limits on the flux of gravitational waves incident on the earth than previous direct measurements. This paper describes the instruments and the data in some detail, as a companion to analysis papers based on the first data.Comment: 41 pages, 9 figures 17 Sept 03: author list amended, minor editorial change

Heavy quarkonium: progress, puzzles, and opportunities

A golden age for heavy quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the $B$-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing investigations. The plethora of newly-found quarkonium-like states unleashed a flood of theoretical investigations into new forms of matter such as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b}, and b\bar{c} bound states have been shown to validate some theoretical approaches to QCD and highlight lack of quantitative success for others. The intriguing details of quarkonium suppression in heavy-ion collisions that have emerged from RHIC have elevated the importance of separating hot- and cold-nuclear-matter effects in quark-gluon plasma studies. This review systematically addresses all these matters and concludes by prioritizing directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K. Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D. Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A. Petrov, P. Robbe, A. Vair