4,945 research outputs found

    An LED-based Flasher System for VERITAS

    Full text link
    We describe a flasher system designed for use in monitoring the gains of the photomultiplier tubes used in the VERITAS gamma-ray telescopes. This system uses blue light-emitting diodes (LEDs) so it can be operated at much higher rates than a traditional laser-based system. Calibration information can be obtained with better statistical precision with reduced loss of observing time. The LEDs are also much less expensive than a laser. The design features of the new system are presented, along with measurements made with a prototype mounted on one of the VERITAS telescopes.Comment: Accepted for publication in Nuclear Instruments and Methods in Physics Research

    Parity violating pion electroproduction off the nucleon

    Get PDF
    Parity violating (PV) contributions due to interference between γ\gamma and Z0Z^0 exchange are calculated for pion electroproduction off the nucleon. A phenomenological model with effective Lagrangians is used to determine the resulting asymmetry for the energy region between threshold and Δ(1232)\Delta(1232) resonance. The Δ\Delta resonance is treated as a Rarita-Schwinger field with phenomenological NΔN \Delta transition currents. The background contributions are given by the usual Born terms using the pseudovector πN\pi N Lagrangian. Numerical results for the asymmetry are presented.Comment: 17 pages, RevTeX, 6 figures (in separate file figs.uu), uses epsf, accepted for publication in Z. Phys.

    Understanding and optimising an identification/brief advice (IBA) service about alcohol in the community pharmacy setting

    Get PDF
    This is the final report of an evaluation into the identification/brief advice (IBA) service about alcohol in community pharmacy settings in the North West of England. Since 2007, almost 100 pharmacies in the North West have - at some point - been commissioned to provide an identification and brief advice (IBA) service for alcohol. This evaluation sought to understand how the service had been adapted for and implemented in the community pharmacy setting, and how its potential might be maximised. Its aims were: 1. To characterise, consolidate and optimise both the constant and variable elements of the pharmacy alcohol identification/brief advice (IBA) service in NHS Northwest, and 2. To inform planning for current and future pharmacy based services promoting safe consumption of alcohol. The evaluation was split into three main workstreams, supported by a preliminary scoping phase, and combined quantitative and qualitative methods: • Descriptive and comparative statistical analysis of pharmacy alcohol IBA data; • In-pharmacy work, including observation of staff engagement with customers, recording consultations between staff and customers, follow-up telephone interviews with customers, and group feedback interviews with pharmacy staff; • Stakeholder engagement through self-completion surveys, semi-structured interviews and a workshop. This report gives the background to the project, and details the methods, results and implications

    Atomic Hydrogen Cleaning of Polarized GaAs Photocathodes

    Full text link
    Atomic hydrogen cleaning followed by heat cleaning at 450∘^\circC was used to prepare negative-electron-affinity GaAs photocathodes. When hydrogen ions were eliminated, quantum efficiencies of 15% were obtained for bulk GaAs cathodes, higher than the results obtained using conventional 600∘^\circC heat cleaning. The low-temperature cleaning technique was successfully applied to thin, strained GaAs cathodes used for producing highly polarized electrons. No depolarization was observed even when the optimum cleaning time of about 30 seconds was extended by a factor of 100

    Recruiting for values in healthcare: a preliminary review of the evidence

    Get PDF
    Displaying compassion, benevolence and respect, and preserving the dignity of patients are important for any healthcare professional to ensure the provision of high quality care and patient outcomes. This paper presents a structured search and thematic review of the research evidence relating to values-based recruitment within healthcare. Several different databases, journals and government reports were searched to retrieve studies relating to values-based recruitment published between 1998 and 2013, both in healthcare settings and other occupational contexts. There is limited published research related to values-based recruitment directly, so the available theoretical context of values is explored alongside an analysis of the impact of value congruence. The implications for the design of selection methods to measure values is explored beyond the scope of the initial literature search. Research suggests some selection methods may be appropriate for values-based recruitment, such as situational judgment tests (SJTs), structured interviews and multiple-mini interviews (MMIs). Personality tests were also identified as having the potential to compliment other methods (e.g. structured interviews), as part of a values-based recruitment agenda. Methods including personal statements, references and unstructured/'traditional' interviews were identified as inappropriate for values-based recruitment. Practical implications are discussed in the context of values-based recruitment in the healthcare context. Theoretical implications of our findings imply that prosocial implicit trait policies, which could be measured by selection tools such as SJTs and MMIs, may be linked to individuals' values via the behaviours individuals consider to be effective in given situations. Further research is required to state this conclusively however, and methods for values-based recruitment represent an exciting and relatively unchartered territory for further research
    • …
    corecore