4,330 research outputs found
A fresh look on the flux tube in Abelian-projected SU(2) gluodynamics
We reconsider the properties of the flux tube within
Abelian-projected SU(2) lattice gauge theory in terms of electric field and
monopole current. In the maximal Abelian gauge we assess the influence of the
Gribov copies on the apparent flux-tube profile. For the optimal gauge fixing
we study the independence of the profile on the lattice spacing for
2.3, 2.4, and 2.5115 on a lattice. We decompose the Abelian Wilson loop
into monopole and photon parts and compare the electric and monopole profile
emerging from different sources with the field strength and monopole current
within the dual Ginzburg-Landau theory.Comment: 3 pages, 6 figures, Lattice2002(topology
Spin-Glass and Chiral-Glass Transitions in a Heisenberg Spin-Glass Model in Three Dimensions
The three-dimensional Heisenberg spin-glass model is investigated by
the non-equilibrium relaxation method from the paramagnetic state. Finite-size
effects in the non-equilibrium relaxation are analyzed, and the relaxation
functions of the spin-glass susceptibility and the chiral-glass susceptibility
in the infinite-size system are obtained. The finite-time scaling analysis
gives the spin-glass transition at and the
chiral-glass transition at . The results
suggest that both transitions occur simultaneously. The critical exponent of
the spin-glass susceptibility is estimated as ,
which makes an agreement with the experiments of the insulating and the
canonical spin-glass materials.Comment: 4 pages, 2 figure
Structural Study of an Amorphous Bi-Fe-Ca-O Thin Film by the Anomalous X-ray Scattering
The structure of the amorphous Bi-Fe-Ca-O film with 0.3 m thick grown on the Si single crystal was studied by the anomalous x-ray scattering (AXS) method. This relatively new method using the anomalous dispersion effect of a specific constituent element in a film reduces the difficulty in the subtraction process of a substrate intensity for estimating the net intensity of a thin film, which becomes a main cause of errors of the resultant data in the conventional method. The environmental radial distribution functions around Bi and Fe in the amorphous Bi-Fe-Ca-O film were determined, from which the structural features were obtained
Redshift-space Distortions of the Power Spectrum of Cosmological Objects on a Light Cone : Explicit Formulations and Theoretical Implications
We examine the effects of the linear and the cosmological redshift-space
distortions on the power spectrum of cosmological objects on a light cone. We
develop theoretical formulae for the power spectrum in linear theory of density
perturbations in a rigorous manner starting from first principle corresponding
to Fourier analysis. Approximate formulae, which are useful properly to
incorporate the redshift-space distortion effects into the power spectrum are
derived, and the validity is examined. Applying our formulae to galaxy and
quasar samples which roughly match the SDSS survey, we will show how the
redshift-space distortions distort the power spectrum on the light cone
quantitatively.Comment: 30 pages, Accepted for publication in the Astrophysical Journal
Supplement Serie
Magnetic Excitations in the Quasi-1D Ising-like Antiferromagnet TlCoCl
Neutron inelastic scattering measurements have been performed in order to
investigate the magnetic excitations in the quasi-1D Ising-like antiferromagnet
TlCoCl. We observed the magnetic excitation, which corresponds to the
spin-wave excitation continuum corresponding to the domain-wall pair excitation
in the 1D Ising-like antiferromagnet. According to the Ishimura-Shiba theory,
we analyzed the observed spin-wave excitation, and the exchange constant
and the anistropy were estimated as 14.7 meV and 0.14 in TlCoCl,
respectively.Comment: 2 pages, 3 figures, jpsj2.cls, to be published in J. Phys. Soc. Jpn.
Vol.75 (2006) No.
Forty-Four Pass Fibre Optic Loop for Improving the Sensitivity of Surface Plasmon Resonance Sensors
A forty-four pass fibre optic surface plasmon resonance sensor that enhances
detection sensitivity according to the number of passes is demonstrated for the
first time. The technique employs a fibre optic recirculation loop that passes
the detection spot forty- four times, thus enhancing sensitivity by a factor of
forty-four. Presently, the total number of passes is limited by the onset of
lasing action of the recirculation loop. This technique offers a significant
sensitivity improvement for various types of plasmon resonance sensors that may
be used in chemical and biomolecule detections.Comment: Submitted for publication; patent disclosure submitte
Towards Identifying and closing Gaps in Assurance of autonomous Road vehicleS - a collection of Technical Notes Part 1
This report provides an introduction and overview of the Technical Topic Notes (TTNs) produced in the Towards Identifying and closing Gaps in Assurance of autonomous Road vehicleS (Tigars) project. These notes aim to support the development and evaluation of autonomous vehicles. Part 1 addresses: Assurance-overview and issues, Resilience and Safety Requirements, Open Systems Perspective and Formal Verification and Static Analysis of ML Systems. Part 2: Simulation and Dynamic Testing, Defence in Depth and Diversity, Security-Informed Safety Analysis, Standards and Guidelines
Measuring our universe from galaxy redshift surveys
Galaxy redshift surveys have achieved significant progress over the last
couple of decades. Those surveys tell us in the most straightforward way what
our local universe looks like. While the galaxy distribution traces the bright
side of the universe, detailed quantitative analyses of the data have even
revealed the dark side of the universe dominated by non-baryonic dark matter as
well as more mysterious dark energy (or Einstein's cosmological constant). We
describe several methodologies of using galaxy redshift surveys as cosmological
probes, and then summarize the recent results from the existing surveys.
Finally we present our views on the future of redshift surveys in the era of
Precision Cosmology.Comment: 82 pages, 31 figures, invited review article published in Living
Reviews in Relativity, http://www.livingreviews.org/lrr-2004-
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