37,545 research outputs found
Inclusive Decay Rate for in Next-to-Leading Logarithmic Order and CP Asymmetry in the Standard Model
We compute the decay rate for the CKM-suppressed electromagnetic penguin
decay (and its charge conjugate) in NLO QCD, including
leading power corrections in and in the standard model. The
average branching ratio of the decay and its charge conjugate
is estimated to be in the range , obtained by varying the CKM-Wolfenstein parameters
and in the range and and taking into account other parametric dependence. In the stated
range of the CKM parameters, we find the ratio to lie in the range between 0.017 and 0.074.
Theoretical uncertainties in this ratio are found to be small. Hence, this
ratio is well suited to provide independent constraints on the CKM parameters.
The CP-asymmetry in the decay rates is found to be in the
range . Both the decay rates and CP asymmetry are measurable in
forthcoming experiments at factories and possibly at HERA-B.Comment: 17 pages including 7 postscript figures; uses epsfig; The changes
w.r.t the previous version are: A comment about the Bremsstrahlung
corrections is added as well as a note on the feasibility of the measurement
$B -> X_d gamma
Enabling adaptive scientific workflows via trigger detection
Next generation architectures necessitate a shift away from traditional
workflows in which the simulation state is saved at prescribed frequencies for
post-processing analysis. While the need to shift to in~situ workflows has been
acknowledged for some time, much of the current research is focused on static
workflows, where the analysis that would have been done as a post-process is
performed concurrently with the simulation at user-prescribed frequencies.
Recently, research efforts are striving to enable adaptive workflows, in which
the frequency, composition, and execution of computational and data
manipulation steps dynamically depend on the state of the simulation. Adapting
the workflow to the state of simulation in such a data-driven fashion puts
extremely strict efficiency requirements on the analysis capabilities that are
used to identify the transitions in the workflow. In this paper we build upon
earlier work on trigger detection using sublinear techniques to drive adaptive
workflows. Here we propose a methodology to detect the time when sudden heat
release occurs in simulations of turbulent combustion. Our proposed method
provides an alternative metric that can be used along with our former metric to
increase the robustness of trigger detection. We show the effectiveness of our
metric empirically for predicting heat release for two use cases.Comment: arXiv admin note: substantial text overlap with arXiv:1506.0825
Complete gluon bremsstrahlung corrections to the process b -> s l+ l-
In a recent paper, we presented the calculation of the order (alpha_s)
virtual corrections to b->s l+ l- and of those bremsstrahlung terms which are
needed to cancel the infrared divergences. In the present paper we work out the
remaining order(alpha_s) bremsstrahlung corrections to b->s l+ l- which do not
suffer from infrared and collinear singularities. These new contributions turn
out to be small numerically. In addition, we also investigate the impact of the
definition of the charm quark mass on the numerical results.Comment: 20 pages including 11 postscript figure
SARS and Security: Health in the 'New Normal'
In "SARS and Security: Health in the "New Normal,"" Claire Hooker and Harris Ali illustrate how the boundaries between public health and national security are being blurred in the present age. The authors show how the "new normal" is an ideology that constructs the world as inherently insecure. Their paper demonstrates how this ideology converges along a number of tangents with neoliberalism that has repercussions for how matters of public health and national security are being reimagined in North America. The new normal, as the authors argue, is a discursive frame that shapes how governments interpret and respond to crises in the aftermath of the 9/11 terrorist attacks and the worldwide outbreak of SARS
SARS and Security: Health in the 'New Normal'
In "SARS and Security: Health in the "New Normal,"" Claire Hooker and Harris Ali illustrate how the boundaries between public health and national security are being blurred in the present age. The authors show how the "new normal" is an ideology that constructs the world as inherently insecure. Their paper demonstrates how this ideology converges along a number of tangents with neoliberalism that has repercussions for how matters of public health and national security are being reimagined in North America. The new normal, as the authors argue, is a discursive frame that shapes how governments interpret and respond to crises in the aftermath of the 9/11 terrorist attacks and the worldwide outbreak of SARS
Mechanism, dynamics, and biological existence of multistability in a large class of bursting neurons
Multistability, the coexistence of multiple attractors in a dynamical system,
is explored in bursting nerve cells. A modeling study is performed to show that
a large class of bursting systems, as defined by a shared topology when
represented as dynamical systems, is inherently suited to support
multistability. We derive the bifurcation structure and parametric trends
leading to multistability in these systems. Evidence for the existence of
multirhythmic behavior in neurons of the aquatic mollusc Aplysia californica
that is consistent with our proposed mechanism is presented. Although these
experimental results are preliminary, they indicate that single neurons may be
capable of dynamically storing information for longer time scales than
typically attributed to nonsynaptic mechanisms.Comment: 24 pages, 8 figure
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