A QCD Sum-Rules Analysis of Vector (1−−1^{--}) Heavy Quarkonium Meson-Hybrid Mixing

We use QCD Laplace sum-rules to study meson-hybrid mixing in vector ($1^{--}$) heavy quarkonium. We compute the QCD cross-correlator between a heavy meson current and a heavy hybrid current within the operator product expansion. In addition to leading-order perturbation theory, we include four- and six-dimensional gluon condensate contributions as well as a six-dimensional quark condensate contribution. We construct several single and multi-resonance models that take known hadron masses as inputs. We investigate which resonances couple to both currents and so exhibit meson-hybrid mixing. Compared to single resonance models that include only the ground state, we find that models that also include excited states lead to significantly improved agreement between QCD and experiment. In the charmonium sector, we find that meson-hybrid mixing is consistent with a two-resonance model consisting of the $J/\psi$ and a 4.3~GeV resonance. In the bottomonium sector, we find evidence for meson-hybrid mixing in the $\Upsilon(1S)$, $\Upsilon(2S)$, $\Upsilon(3S)$, and $\Upsilon(4S)$.Comment: Updated version includes extended analysi

Close-packed structures and phase diagram of soft spheres in cylindrical pores

It is shown for a model system consisting of spherical particles confined in cylindrical pores that the first ten close-packed phases are in one-to-one correspondence with the first ten ways of folding a triangular lattice, each being characterized by a roll-up vector like the single-walled carbon nanotube. Phase diagrams in pressure-diameter and temperature-diameter planes are obtained by inherent-structure calculation and molecular dynamics simulation. The phase boundaries dividing two adjacent phases are infinitely sharp in the low-temperature limit but are blurred as temperature is increased. Existence of such phase boundaries explains rich, diameter-sensitive phase behavior unique for cylindrically confined systems

Are we Bridging the Divide in IWO Psychology?

This paper examines the knowledge transfer process within the profession of work and organisational psychology. In consonance with the theme of the 2011 congress, it considers the extent to which proposed ‘bridging mechanisms’ can provide useful vehicles for operationalising the pursuit of the dual goal of improving both the well-being of individuals and the effectiveness of work organizations. It considers the way in which the profession attempts to ground its concepts in a sound evidence base and then successfully mobilise this knowledge at the interface of research and practice. It does so by critically examining the scientist-practitioner model and the ways in which this model can be operationalised by practitioners and researchers. The criticism which is aimed at academics is that their research is irrelevant; it explores narrow concepts too often with student samples. Practitioners, on the other hand, are accused of too infrequently bringing scientific findings from the research literature to their practice. The problem has been cast in terms of both one of knowledge production and also knowledge transfer and is typified, at least in one direction – the impact of research upon practice, by what has in other professions, most notably medicine and more recently management, been called evidence-based practice. Denise Rousseau, in her 2005 presidential address to the American Academy of Management defined evidence-based management (EBM) as “translating principles based on best evidence into organizational practices” and there have been a number of attempts to invoke a similar model of evidence-based practice in the field of work and organisational psychology. In 2007 Anderson described the academic-practitioner divide as ‘natural’, suggesting the way forward was to focus on ‘bridging mechanisms’ describing six which had been proposed at the 1995 SIOP conference. What is the situation over decade later? To what extent have these bridges been built? This paper explores the nature and extent of these bridges by presenting case studies and findings from a UK survey of IWO psychologists

Density Functional Theory of Inhomogeneous Liquids: II. A Fundamental Measure Approach

Previously, it has been shown that the direct correlation function for a Lennard-Jones fluid could be modeled by a sum of that for hard-spheres, a mean-field tail and a simple linear correction in the core region constructed so as to reproduce the (known) bulk equation of state of the fluid(Lutsko, JCP 127, 054701 (2007)). Here, this model is combined with ideas from Fundamental Measure Theory to construct a density functional theory for the free energy. The theory is shown to accurately describe a range of inhomogeneous conditions including the liquid-vapor interface, the fluid in contact with a hard wall and a fluid confined in a slit pore. The theory gives quantitatively accurate predictions for the surface tension, including its dependence on the potential cutoff. It also obeys two important exact conditions: that relating the direct correlation function to the functional derivative of the free energy with respect to density, and the wall theorem.Comment: to appear in J. Chem. Phy

On the Standard Approach to Renormalization Group Improvement

Two approaches to renormalization-group improvement are examined: the substitution of the solutions of running couplings, masses and fields into perturbatively computed quantities is compared with the systematic sum of all the leading log (LL), next-to-leading log (NLL) etc. contributions to radiatively corrected processes, with n-loop expressions for the running quantities being responsible for summing N^{n}LL contributions. A detailed comparison of these procedures is made in the context of the effective potential V in the 4-dimensional O(4) massless $\lambda \phi^{4}$ model, showing the distinction between these procedures at two-loop order when considering the NLL contributions to the effective potential V.Comment: 6 page

The Automatic Real-Time GRB Pipeline of the 2-m Liverpool Telescope

The 2-m Liverpool Telescope (LT), owned by Liverpool John Moores University, is located in La Palma (Canary Islands) and operates in fully robotic mode. In 2005, the LT began conducting an automatic GRB follow-up program. On receiving an automatic GRB alert from a Gamma-Ray Observatory (Swift, INTEGRAL, HETE-II, IPN) the LT initiates a special override mode that conducts follow-up observations within 2-3 min of the GRB onset. This follow-up procedure begins with an initial sequence of short (10-s) exposures acquired through an r' band filter. These images are reduced, analyzed and interpreted automatically using pipeline software developed by our team called "LT-TRAP" (Liverpool Telescope Transient Rapid Analysis Pipeline); the automatic detection and successful identification of an unknown and potentially fading optical transient triggers a subsequent multi-color imaging sequence. In the case of a candidate brighter than r'=15, either a polarimetric (from 2006) or a spectroscopic observation (from 2007) will be triggered on the LT. If no candidate is identified, the telescope continues to obtain z', r' and i' band imaging with increasingly longer exposure times. Here we present a detailed description of the LT-TRAP and briefly discuss the illustrative case of the afterglow of GRB 050502a, whose automatic identification by the LT just 3 min after the GRB, led to the acquisition of the first early-time (< 1 hr) multi-color light curve of a GRB afterglow.Comment: PASP, accepted (8 pages, 3 figures

Development and validation of the Xhosa translations of the Beck Inventories: 1. Challenges of the translation process

This article describes the translation of the Beck Depression Inventory-II, the Beck Hopeless Scale, and the Beck Anxiety Inventory, into Xhosa the language spoken in the Eastern Cape of South Africa. The processes of translation, back-translation and committee discussion failed to yield trustworthy translations because of practical difficulties in working with translators. Critical words and phrases were identified which gave rise to lack of agreement. For each, a range of options was generated and the advantages and disadvantages evaluated in terms of criteria such as conceptual and idiomatic equivalence, and extensiveness of usage. Examples are given of the problems encountered and the way in which final decisions were made. A pilot clinical trial demonstrated the acceptability of the translated Instruments. Two further articles report the psychometric evaluation of the translated scales