15,175 research outputs found
Magnetic moments and electromagnetic radii of nucleon and in an extended GBE model
We derive the exchange currents of pseudoscalar, vector, and scalar mesons
from Feynman diagrams, and use them to calculate the magnetic form factors of
nucleon and . The magnetic moments and electromagnetic radii are
obtained by using those form factors and the parameters determined from the
masses of nucleon and . We find the magnetic moments and
electromagnetic radii of nucleon and can be produced very well
in the extended Goldstone-boson-exchange model (GBE) in which all of
pseudoscalar, vector and scalar meson nonet are included. The magnetic moments
of are closer to experiment values and results from lattice
calculation than the results obtained by the model without other mesons except
for pion and sigma.Comment: 15 pages,5 figure
Regularizing the quark-level model
We show that the finite difference, , between quadratic and
logarithmic divergent integrals ,
as encountered in the linear model, is in fact regularization
independent.Comment: 9 pages, 2 figures, Latex, to appear in Mod. Phys. Lett.
decays revisited: branching ratios and T-odd momenta correlations
We calculate the branching ratios of the decays, and the T-odd triple momenta correlations
, due to the
electromagnetic final state interaction, in these processes. The contributions
on the order of and to the corresponding amplitudes
are treated exactly. For the branching ratios, the corrections on the order of
are estimated and demonstrated to be small. We compare the results
with those of other authors. In some cases our results differ considerably from
the previous ones.Comment: 13 pages, 11 figures; references adde
Minimal Length Uncertainty Relation and Hydrogen Atom
We propose a new approach to calculate perturbatively the effects of a
particular deformed Heisenberg algebra on energy spectrum. We use this method
to calculate the harmonic oscillator spectrum and find that corrections are in
agreement with a previous calculation. Then, we apply this approach to obtain
the hydrogen atom spectrum and we find that splittings of degenerate energy
levels appear. Comparison with experimental data yields an interesting upper
bound for the deformation parameter of the Heisenberg algebra.Comment: 7 pages, REVTe
Model for Small neutrino masses at the TeV Scale
We propose a model for neutrino mass generation in wich no physics beyond a
TeV is required. We extend the standard model by adding two charged singlet
fields with lepton number two. Dirac neutrino masses are
generated at the one loop level. Small left handed majorana neutrino masses can
be generated via the seesaw mechanism with right handed neutrino masses
are of order TeV scale.Comment: 13 pages, 2 figure
The Serums Tool-Chain:Ensuring Security and Privacy of Medical Data in Smart Patient-Centric Healthcare Systems
Digital technology is permeating all aspects of human society and life. This leads to humans becoming highly dependent on digital devices, including upon digital: assistance, intelligence, and decisions. A major concern of this digital dependence is the lack of human oversight or intervention in many of the ways humans use this technology. This dependence and reliance on digital technology raises concerns in how humans trust such systems, and how to ensure digital technology behaves appropriately. This works considers recent developments and projects that combine digital technology and artificial intelligence with human society. The focus is on critical scenarios where failure of digital technology can lead to significant harm or even death. We explore how to build trust for users of digital technology in such scenarios and considering many different challenges for digital technology. The approaches applied and proposed here address user trust along many dimensions and aim to build collaborative and empowering use of digital technologies in critical aspects of human society
Study of excited nucleon states at EBAC: status and plans
We present an overview of a research program for the excited nucleon states
in Excited Baryon Analysis Center (EBAC) at Jefferson Lab. Current status of
our analysis of the meson production reactions based on the unitary dynamical
coupled-channels model is summarized, and the N* pole positions extracted from
the constructed scattering amplitudes are presented. Our plans for future
developments are also discussed.Comment: Plenary talk given at Workshop on the Physics of Excited Nucleon --
NSTAR2009, Beijing, April 19-22, 2009. 8 pages, 8 figure
On the gluon content of the eta and eta' mesons
A phenomenological analysis of radiative and
decays is performed with the purpose of determining the gluonic content of the
and wave functions. Our results show that within our model
there is no evidence for a gluonium contribution in the ,
, or the , . In terms of a mixing angle description this corresponds to
and . In
addition, the - mixing angle is found to be if we don't allow for a gluonium component.Comment: 16 pages, 3 figures, JHEP style. First part of data fitting changed,
conclusions not modifie
Task Scheduling of Processor Pipelines with Application to Network Processors
Chip Multi-Processors (CMPs) are now available in a variety of systems and provide the opportunity for achieving high computational performance by exploiting application-level parallelism. In the communications environment, network processors (NPs) are often designed around CMP architectures and in this context the processors may be used in a pipelined manner. This leads to the issue of scheduling tasks on processor pipelines. This paper considers problems associated with determining optimal application task assignments for such pipelines. A system and algorithm called Greedy Pipe is presented and its performance analyzed. The algorithm employs a greedy heuristic to schedule tasks derived from multiple application flows on pipelines with an arbitrary number of stages. Tasks associated with multiple applications may also be shared. Experimental results indicate that over a wide range of conditions, 95% of the time Greedy Pipe quickly obtains schedules within 10% of optimal
Phase space constraints and statistical jet studies in heavy-ion collisions
The effect of the correlation induced by global momentum conservation on the
two-particle distribution in nucleus-nucleus collisions is discussed, with a
focus on the generic case of collisions with a non-vanishing impact parameter.Comment: 5 pages, invited talk at the RHIC & AGS Annual Users' Meeting,
Brookhaven Nat. Lab. (USA) and at the EPS HEP 2007 Conference, Manchester
(UK
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