3,628 research outputs found
Towards New Frontiers with Decays
Exploring correlations between the CP asymmetries of
following from an isospin relation, we uncover new tensions with the Standard
Model in data for neutral decays. Should this intriguing picture
originate from New Physics, a modified electroweak penguin sector provides a
key scenario. It includes models with extra bosons, which offer attractive
ways to resolve anomalies in measurements. We
present a new strategy to reveal the underlying physics, apply it to current
data, and discuss the excellent prospects for Belle II.Comment: 7 pages, 3 figure
Appendices to Kunitz on mortality calculations
Appendices to "What Yugoslavia means: progress, nationalism, and health" by Stephen Kunit
Policy Areas Impinging on Elderly Transportation Mobility: An Explanation with Ontario, Canada as Example
As countries face the challenges posed by rising numbers of older persons, the need to reassess their respective policies to address transport needs in aging societies is increasingly recognized in relation to health and sustainability goals. This paper proposes the examination of six interrelated policy areas affecting elderly mobility in a country or administrative region. A general survey of policy developments in each of these areas could improve current strategies and existing processes in the planning and implementation of mobility services that will be responsive to both elderly and the general population now and in the future. These include: 1) general transport policy framework; 2) travel mode preference; 3) alternative transport infrastructure stock and investments; 4) housing-land-use-transportation linkage; 5) research and technology applications that improve travel mode and environment; and 6) institutional and legal reforms. These policy areas are discussed and given concrete elucidation in the case of Ontario, Canada. Reflections and recommendations for further research and policy action deemed critical in the case region are highlighted.transportation, aging, regional policy, Canada
Quantum description of surface-enhanced resonant Raman scattering within a hybrid-optomechanical model
Surface-Enhanced Raman Scattering (SERS) allows for detection and
identification of molecular vibrational fingerprints in minute sample
quantities. The SERS process can be also exploited for optical manipulation of
molecular vibrations. We present a quantum description of Surface-Enhanced
Resonant Raman scattering (SERRS), in analogy to hybrid cavity optomechanics,
and compare the resonant situation with the off-resonant SERS. Our model
predicts the existence of a regime of coherent interaction between electronic
and vibrational degrees of freedom of a molecule, mediated by a plasmonic
nanocavity. This coherent mechanism can be achieved by parametrically tuning
the frequency and intensity of the incident pumping laser and is related to the
optomechanical pumping of molecular vibrations. We find that vibrational
pumping is able to selectively activate a particular vibrational mode, thus
providing a mechanism to control its population and drive plasmon-assisted
chemistry
Periodically driven Taylor-Couette turbulence
We study periodically driven Taylor-Couette turbulence, i.e. the flow
confined between two concentric, independently rotating cylinders. Here, the
inner cylinder is driven sinusoidally while the outer cylinder is kept at rest
(time-averaged Reynolds number is ). Using particle image
velocimetry (PIV), we measure the velocity over a wide range of modulation
periods, corresponding to a change in Womersley number in the range . To understand how the flow responds to a given modulation, we
calculate the phase delay and amplitude response of the azimuthal velocity.
In agreement with earlier theoretical and numerical work, we find that for
large modulation periods the system follows the given modulation of the
driving, i.e. the system behaves quasi-stationary. For smaller modulation
periods, the flow cannot follow the modulation, and the flow velocity responds
with a phase delay and a smaller amplitude response to the given modulation. If
we compare our results with numerical and theoretical results for the laminar
case, we find that the scalings of the phase delay and the amplitude response
are similar. However, the local response in the bulk of the flow is independent
of the distance to the modulated boundary. Apparently, the turbulent mixing is
strong enough to prevent the flow from having radius-dependent responses to the
given modulation.Comment: 12 pages, 6 figure
Concurrent Geometric Multicasting
We present MCFR, a multicasting concurrent face routing algorithm that uses
geometric routing to deliver a message from source to multiple targets. We
describe the algorithm's operation, prove it correct, estimate its performance
bounds and evaluate its performance using simulation. Our estimate shows that
MCFR is the first geometric multicast routing algorithm whose message delivery
latency is independent of network size and only proportional to the distance
between the source and the targets. Our simulation indicates that MCFR has
significantly better reliability than existing algorithms
The hard X-ray tails in neutron star low mass X-ray binaries: BeppoSAX observations and possible theoretical explanation of the GX 17+2 case
We report results of a new spectral analysis of two BeppoSAX observations of
the Z source GX 17+2. In one of the two observations the source exhibits a
powerlaw-like hard (> 30 keV) X-ray tail which was described in a previous work
by a hybrid Comptonization model. Recent high-energy observations with INTEGRAL
of a sample of Low Mass X-Ray Binaries including both Z and atoll classes have
shown that bulk (dynamical) Comptonization of soft photons can be a possible
alternative mechanism for producing hard X-ray tails in such systems. We start
from the INTEGRAL results and we exploit the broad-band capability of BeppoSAX
to better investigate the physical processes at work. We use GX 17+2 as a
representative case. Moreover, we suggest that weakening (or disappearance) of
the hard X-ray tail can be explained by increasing radiation pressure
originated at the surface of the neutron star (NS). As a result the high
radiation pressure stops the bulk inflow and consequently this radiation
feedback of the NS surface leads to quenching the bulk Comptonization.Comment: 6 pages, 3 figures, Accepted for publication in Ap
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