7,881 research outputs found
Exclusive W^+ + photon production in proton-antiproton collisions II: results
We present results for total cross sections, single and double differential
distributions and correlations between pairs of outgoing particles in the
reactions p + antip --> W^+ + photon and p + antip --> W^+ + photon + jet at
sqrt(S)=1.8 TeV. Order alpha-strong QCD corrections and leading logarithm
photon bremsstrahlung contributions are included in the MS-bar mass
factorization scheme for three experimental scenarios: 1) 2-body inclusive
production of W^+ and photon, 2) exclusive production of W^+, photon and 1 jet
and 3) exclusive production of W^+ and photon with 0 jet.
The latest CTEQ parton distribution functions, which fit the newly released
HERA data, are used in our analysis. The dependence of our results on the mass
factorization scale is used to place error bars on our predictions for the
single differential distributions and correlations.Comment: 15 pages (LateX). 50 pages of postscript figures available via ftp
anonymous from max.physics.sunysb.edu in the directory
preprints/mendoza/EXCLUSIVE_W_GAMMA_II.dir (files named fig_*.ps)
ITP-SB-93-80. ([email protected])([email protected]
Lattice Boltzmann scheme for relativistic fluids
A Lattice Boltzmann formulation for relativistic fluids is presented and
numerically verified through quantitative comparison with recent hydrodynamic
simulations of relativistic shock-wave propagation in viscous quark-gluon
plasmas. This formulation opens up the possibility of exporting the main
advantages of Lattice Boltzmann methods to the relativistic context, which
seems particularly useful for the simulation of relativistic fluids in
complicated geometries.Comment: Submitted to PR
Derivation of the Lattice Boltzmann Model for Relativistic Hydrodynamics
A detailed derivation of the Lattice Boltzmann (LB) scheme for relativistic
fluids recently proposed in Ref. [1], is presented. The method is numerically
validated and applied to the case of two quite different relativistic fluid
dynamic problems, namely shock-wave propagation in quark-gluon plasmas and the
impact of a supernova blast-wave on massive interstellar clouds. Close to
second order convergence with the grid resolution, as well as linear dependence
of computational time on the number of grid points and time-steps, are
reported
Exclusive W + photon production in proton-antiproton collisions I: general formalism
We present a detailed computation of the fully exclusive cross section of p +
antip --> W + photon + X with X = 0 and 1 jet in the framework of the
factorization theorem and dimensional regularization. Order alpha-strong and
photon bremsstrahlung contributions are discussed in the MS-bar mass
factorization scheme. The resulting expressions are ready to be implemented
numerically using Monte Carlo techniques to compute single and double
differential cross sections and correlations between outgoing pairs of
particles.Comment: ITP-SB-93-72, 40 pages, LateX. 3*4 figures in separate file.
([email protected]) ([email protected]
Transport enhancement from incoherent coupling between one-dimensional quantum conductors
We study the non-equilibrium transport properties of a highly anisotropic
two-dimensional lattice of spin-1/2 particles governed by a Heisenberg XXZ
Hamiltonian. The anisotropy of the lattice allows us to approximate the system
at finite temperature as an array of incoherently coupled one-dimensional
chains. We show that in the regime of strong intrachain interactions, the weak
interchain coupling considerably boosts spin transport in the driven system.
Interestingly, we show that this enhancement increases with the length of the
chains, which is related to superdiffusive spin transport. We describe the
mechanism behind this effect, compare it to a similar phenomenon in single
chains induced by dephasing, and explain why the former is much stronger
A framework for automated conflict detection and resolution in medical guidelines
This research is supported by the MRC-funded UK Research and Innovation grant MR/S003819/1 and by EPSRC grant EP/M014290/1.Common chronic conditions are routinely treated following standardised procedures known as clinical guidelines. For patients suffering from two or more chronic conditions, known as multimorbidity, several guidelines have to be applied simultaneously, which may lead to severe adverse effects when the combined recommendations and prescribed medications are inconsistent or incomplete. This paper presents an automated formal framework to detect, highlight and resolve conflicts in the treatments used for patients with multimorbidities focusing on medications. The presented extended framework has a front-end which takes guidelines captured in a standard modelling language and returns the visualisation of the detected conflicts as well as suggested alternative treatments. Internally, the guidelines are transformed into formal models capturing the possible unfoldings of the guidelines. The back-end takes the formal models associated with multiple guidelines and checks their correctness with a theorem prover, and inherent inconsistencies with a constraint solver. Key to our approach is the use of an optimising constraint solver which enables us to search for the best solution that resolves/minimises conflicts according to medication efficacy and the degree of severity in case of harmful combinations, also taking into account their temporal overlapping. The approach is illustrated throughout with a real medical example.Publisher PDFPeer reviewe
Disease Surveillance Networks Initiative Asia: Final Evaluation
The DSN Initiative was launched in 2007 under the new strategy of the Rockefeller Foundation. The initiative intends:[1] To improve human resources for disease surveillance in developing countries, thus bolstering national capacity to monitor, report, and respond to outbreaks;[2] To support regional networks to promote collaboration in disease surveillance and response across countries; and[3] To build bridges between regional and global monitoring effortsThe purpose of the DSN evaluation in the Mekong region was twofold:[1]To inform the work and strategy of the Foundation, its grantees, and the broader field of disease surveillance, based on the experience of DSN investments in the Mekong region. More specifically, the evaluation will inform future directions and strategies for current areas of DSN Initiative work, particularly in Asia, and will highlight potential new areas of work and strategy; and[2] To provide accountability to the Rockefeller Foundation's board, staff, and stakeholders for the DSN funds spent in the Mekong region
The secondary minimum in YY Her: Evidence for a tidally distorted giant
We present and analyze quiescent UBVRI light curves of the classical
symbiotic binary YY Her. We show that the secondary minimum, which is clearly
visible only in the quiescent VRI light curves, is due to ellipsoidal
variability of the red giant component. Our simple light curve analysis, by
fitting of the Fourier cosine series, resulted in a self-consistent
phenomenological model of YY Her, in which the periodic changes can be
described by a combination of the ellipsoidal changes and a sinusoidal changes
of the nebular continuum and line emission.Comment: 5 pages, 2 figures, to appear in Astronomy & Astrophysic
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